Title :
Triple GEM detectors for the forward tracker in STAR
Author :
Simon, F. ; Kelsey, J. ; Kohl, M. ; Majka, R. ; Plesko, M. ; Underwood, D. ; Sakuma, T. ; Smirnov, N. ; Spinka, H. ; Surrow, B.
Author_Institution :
Max-Planck-Inst. fur Phys., Munich
Abstract :
Future measurements of the flavor-separated spin structure of the proton via parity-violating W boson production at RHIC require an upgrade of the forward tracking system of the STAR detector. This upgrade will allow the reconstruction of the charge sign of electrons and positrons produced from decaying W bosons. A design based on six large area triple GEM disks using GEM foils produced by Tech-Etch Inc. has emerged as a cost-effective solution to provide the necessary tracking precision. We report first results from a beam test of three test detectors using Tech-Etch produced GEM foils and a laser etched two dimensional strip readout. The detectors show good operational stability, high efficiency and a spacial resolution of around 70 mum or better, exceeding the requirements for the forward tracking upgrade. The influence of the angle of incidence of the particles on the spatial resolution of the detectors has also been studied in detail.
Keywords :
electron multiplier detectors; gas scintillation detectors; position sensitive particle detectors; GEM foils; RHIC; STAR; W boson decay; electrons; flavor-separated proton spin structure; forward tracking system; gas electron multiplier; parity-violating W boson production; positrons; triple GEM detectors; two-dimensional strip readout; Detectors; Electrons; Etching; Laser beams; Positrons; Production systems; Protons; Spatial resolution; Strips; Testing;
Conference_Titel :
Nuclear Science Symposium Conference Record, 2007. NSS '07. IEEE
Print_ISBN :
978-1-4244-0922-8
Electronic_ISBN :
1095-7863
DOI :
10.1109/NSSMIC.2007.4436321
