Electron / pion separation with the H1 LAr calorimeters

Abstract The performances of the H1 liquid argon calorimeter modules for the energy measurements and identification of electrons are studied with test data taken at CERN in the energy range 5 to 166 GeV. Various electron identificationestimators exploiting global or detailed showercharacteristics are studied and compared. The usage of impact position measurements is also discussed. A best combination of robust showerestimators leads typically to π-misidentification probabilities in the range 1.5 to 5.0 × 10 −3 at 30 GeV for 95% electron detection efficiency. This further reduces to ∼ 10 −4 for these pions to be misidentified as electrons below 25 GeV.