Charged Pion Energy Reconstruction in the ATLAS Barrel Calorimeter

Abstract

The intrinsic performance of the ATLAS barrel and extended barrel calorimeters for the measurement of charged pions is presented. Pion energy scans (E = 20, 50, 200, 400 and 1000 GeV) at two pseudo-rapidity points ($\eta$ = 0.3 and 1.3) and pseudorapidity scans ($-0.2 < \eta < 1.8$) with pions of constant transverse energy ($E_T = 20$ and 50 GeV) are analysed. A simple approach, that accounts in first order for non-compensation and dead material effects, is used for the pion energy reconstruction. The intrinsic performances of the calorimeter are studied: resolution, linearity, effect of dead material, tails in the energy distribution. The effect of electronic noise, cell energy cuts and restricted cone size are investigated.