The VENUS-TRD is a cylindrical transition radiation detector, extending from 127 cm to 157.7 cm radially and 296 cm axially. It is designed to improve the e/π separation capability of the VENUS detector by a factor of 10 in order to complement the lead glass calorimeter. It covers an angular region of |cos θ| < 0.68 and contains four layers of radiators and X-ray chambers. It has been working very stably since it started data-taking at the TRISTAN e+e- storage ring in June, 1991. The pion rejection power (Rπ = 1 επ) at an electron efficiency of 90% is Rπ = 10±1 and 15±2 for isolated tracks with a momentum range of 1 < P < 3 and 3 < P < 10 GeV/c, respectively. It decreases to Rπ = 7±1 for tracks with P > 1 GeV/c in hadronic events due to overlap of the tracks in the chamber cells of the TRD. The VENUS-TRD is the largest TRD to perform in colliding beam experiments.
ASJC Scopus subject areas
- Nuclear and High Energy Physics