The CERES/NA45 radial drift Time Projection Chamber

Abstract The design, calibration, and performance of the first radial drift Time Projection Chamber (TPC) are presented. The TPC was built and installed at the CERES/NA45 experiment at the CERN SPS in the late nineties, with the objective to improve the momentum resolution of the spectrometer. The upgraded experiment took data twice, in 1999 and in 2000. After a detailed study of residual distortions a spatial resolution of 340 μ m in the azimuthal and 640 μ m in the radial direction was achieved, corresponding to a momentum resolution of Δ p / p = ( 1 % · p / GeV ) 2 + ( 2 % ) 2 .