The planned tracking upgrade of the STAR experiment at RHIC includes a large-area GEM tracker used to determine the charge sign of electrons and positrons produced from W+(-) decays. For such a large-scale project commercial availability of GEM foils is necessary. We report first results obtained with a triple GEM detector using GEM foils produced by Tech-Etch Inc. of Plymouth, MA, USA. Measurements of gain uniformity, long-term stability as well as measurements of the energy resolution for X-Rays are compared to results obtained with an identical detector using GEM foils produced at CERN. A quality assurance procedure based on optical tests using an automated high-resolution scanner has been established, allowing a study of the correlation of the observed behavior of the detector and the geometrical properties of the GEM foils. Detectors based on Tech-Etch and CERN produced foils both show good uniformity of the gain over the active area and stable gain after an initial charge-up period, making them well suited for precision tracking applications.
@article{arxiv.0707.2543,
title = {Development of Tracking Detectors with industrially produced GEM Foils},
author = {F. Simon and B. Azmoun and U. Becker and L. Burns and D. Crary and K. Kearney and G. Keeler and R. Majka and K. Paton and G. Saini and N. Smirnov and B. Surrow and C. Woody},
journal= {arXiv preprint arXiv:0707.2543},
year = {2008}
}
Comments
6 pages, 14 figures, published in IEEE Transactions on Nuclear Science, v2 updated text and figures