Space charge in drift chambers operated with the Xe,CO2(15%) mixture

Abstract

Using prototype modules of the ALICE Transition Radiation Detector we investigate space charge effects and the dependence of the pion rejection performance on the incident angle of the ionizing particle. The average pulse height distributions in the drift chambers operated with the Xe,CO2(15%) mixture provide quantitative information on the gas gain reduction due to space charge accumulating during the drift of the primary ionization. Our results demonstrate that the pion rejection performance of a TRD is better for tracks which are not at normal incidence to the anode wires. We present detailed simulations of detector signals, which reproduce the measurements and lend strong support to our interpretation of the measurements in terms of space charge effects.

18 pages, 10 figures, accepted for publication in Nucl.Instrum.Meth. A. Data files available at http://www-alice.gsi.de/trd

References in corpus (5)

• Space charge in ionization detectors and the NA48 calorimeter
• Energy loss of pions and electrons of 1 to 6 GeV/c in drift chambers operated with Xe,CO2(15%)
• Pulse height measurements and electron attachment in drift chambers operated with Xe,CO2 mixtures
• Prototype tests for the ALICE TRD
• High Rate Performance of Drift Tubes

Cited by in corpus (5)

• Measurement of electrons from semileptonic heavy-flavour hadron decays in pp collisions at $\sqrt{s}$= 7 TeV
• Transition Radiation Spectra of Electrons from 1 to 10 GeV/c in Regular and Irregular Radiators
• Position Reconstruction in Drift Chambers operated with Xe, CO2 (15%)
• Monte Carlo Simulations of the Transition Radiation Detector of the AMS-02 Experiment
• Development and characterization of MPGD-based transition radiation detectors