Development of a triple GEM UV-photon detector operated in pure CF 4 for the PHENIX experiment
Abstract
Results obtained with a triple Gas Electron Multiplier (GEM) detector operated in pure CF 4 with and without a reflective CsI photocathode are presented. The detector operates in a stable mode at gains up to 10 4. A deviation from exponential growth starts to develop when the total charge exceeds ∼4×10 6 e leading to gain saturation when the total charge is ∼2×10 7 e and making the structure relatively robust against discharges. No aging effects are observed in the GEM foils after a total accumulated charge of ∼10 mC/cm2 at the anode. The ion back-flow current to the reflective photocathode is comparable to the electron current to the anode. However, no significant degradation of the CsI photocathode is observed for a total ion back-flow charge of ∼7 mC/cm2.
- Publication:
-
Nuclear Instruments and Methods in Physics Research A
- Pub Date:
- May 2004
- DOI:
- 10.1016/j.nima.2003.12.018
- arXiv:
- arXiv:physics/0309013
- Bibcode:
- 2004NIMPA.523..345K
- Keywords:
-
- GEM;
- CsI photocathode;
- UV-photon detector;
- CF4;
- HBD;
- Physics - Instrumentation and Detectors
- E-Print:
- 14 pages, 11 figures, Submitted to NIM A