Spatial precision of H1 radial wire drift chambers using gas mixtures suitable for transition radiation detection

Abstract

Results are presented from calibration and tests of a radial wire drift chamber for the H1 experiment at the HERA ep collider. The chambers form part of the H1 forward track detector (FTD) and are designed both to determine accurate vector track segments and to identify simultaneously electrons by means of dEdx measurement and transition radiation (TR) detection. The spatial reconstruction accuracy (from drift timing and charge division) has been investigated using gas mixtures suitable for TR X-ray detection. A novel technique for enhancing the precision of determination of the radial (non-drift) coordinate of each track using the drift cell geometry is evaluated. A brief summary of the performance of the three radial wire chambers in the FTD is given.