Position resolution and particle identification with the ATLAS EM calorimeter

J. Colas (1) , L. Di Ciaccio (1) , M. El Kacimi (1) , O. Gaumer (1) , M. Gouanère (1) , D. Goujdami (1) , R. Lafaye (1) , C. Le Maner (1) , L. Neukermans (1) , P. Perrodo (1) , L. Poggioli (1) , D. Prieur (1) , H. Przysiezniak (1) , G. Sauvage (1) , I. Wingerter-Seez (1) , R. Zitoun (1) , F. Lanni , H. Ma , S. Rajagopalan , S. Rescia , H. Takai , A. Belymam , D. Benchekroun , M. Hakimi , A. Hoummada , E. Barberio , Y.S. Gao , L. Lu , R. Stroynowski , M. Aleksa , J. Beck Hansen , T. Carli , P. Fassnacht , F. Gianotti , L. Hervas , W. Lampl , B. Belhorma (2) , J. Collot (2) , M.L. Gallin-Martel (2) , J.Y. Hostachy (2) , F. Ledroit-Guillon (2) , P. Martin (2) , F. Ohlsson-Malek (2) , S. Saboumazrag (2) , S. Viret (2) , M. Leltchouk , J.A. Parsons , M. Seman , F. Barreiro , J. del Peso , L. Labarga , C. Oliver , S. Rodier , P. Barrillon (3) , C. Benchouk (3) , F. Djama (3) , P.Y. Duval (3) , F. Henry-Couannier (3) , F. Hubaut (3) , E. Monnier (3) , P. Pralavorio (3) , D. Sauvage (3) , C. Serfon (3) , S. Tisserant (3) , J. Toth (3) , D. Banfi (3) , L. Carminati (3) , D. Cavalli (3) , G. Costa (3) , M. Delmastro (3) , M. Fanti (3) , L. Mandelli (3) , M. Mazzanti (3) , G.F. Tartarelli (3) , K. Kotov , A. Maslennikov , G. Pospelov , Yu. Tikhonov , C. Bourdarios (4) , C. de La Taille (4) , L. Fayard (4) , D. Fournier (4) , L. Iconomidou-Fayard (4) , M. Kado (4) , M. Lechowski (4) , G. Parrour (4) , P. Puzo (4) , D. Rousseau (4) , R. Sacco (4) , N. Seguin-Moreau (4) , L. Serin (4) , G. Unal (4) , D. Zerwas (4) , B. Dekhissi , J. Derkaoui , A. El Kharrim , F. Maaroufi , A. Camard (5) , D. Lacour (5) , B. Laforge (5) , I. Nikolic-Audit (5) , P. Schwemling (5) , H. Ghazlane , R. Cherkaoui El Moursli , A. Idrissi Fakhr-Eddine , M. Boonekamp , B. Mansoulié , P. Meyer , J. Schwindling , B. Lund-Jensen , Y. Tayalati

1 LAPP - Laboratoire d'Annecy de Physique des Particules
2 LPSC - Laboratoire de Physique Subatomique et de Cosmologie
3 CPPM - Centre de Physique des Particules de Marseille
4 LAL - Laboratoire de l'Accélérateur Linéaire
5 LPNHE - Laboratoire de Physique Nucléaire et de Hautes Énergies

In the years between 2000 and 2002 several pre-series and series modules of the ATLAS EM barrel and end-cap calorimeter were exposed to electron, photon and pion beams. The performance of the calorimeter with respect to its finely segmented first sampling has been studied. The polar angle resolution has been found to be in the range 50–60 $(mrad)/\sqrt{E(GeV)}$. The $\pi^0$ rejection has been measured to be about 3.5 for 90\% photon selection efficiency at $\rho_T$=50GeV. $e–\pi$ separation studies have indicated that a pion fake rate of (0.07–0.5)\% can be achieved while maintaining 90\% electron identification efficiency for energies up to 40 GeV.

Mots clés: Calorimeters; Particle physics

Domaines: Instrumentations et Détecteurs [physics.ins-det]

J. Colas, L. Di Ciaccio, M. El Kacimi, O. Gaumer, M. Gouanère, et al.. Position resolution and particle identification with the ATLAS EM calorimeter. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2005, 550, pp.96-115. ⟨10.1016/j.nima.2005.05.041⟩. ⟨in2p3-00024451⟩