The STAR collaboration is preparing a tracking detector upgrade, the Forward GEM Tracker (FGT), which will focus on novel spin physics measurements in high-energy polarized proton-proton collisions at RHIC at BNL at a center-of-mass energy of 500 GeV, determining the flavor dependence ($Delta bar{u}$ versus $Delta bar{d}$) of the polarized sea. STAR plans to probe these polarized distribution functions using parity violating W production in the electron/positron decay mode.
This upgrade will consist of six triple-GEM detectors with two dimensional readout arranged in disks along the beam axis. The FGT project requires large GEM foils (~40×40 cm^2) partially manufactured by Tech-Etch Inc. and CERN. The two dimensional readout is based on a chemically etched readout foil based on r-phi geometry coupled to a APV25-S1 chip readout system.
The FGT design, assembly and installation will be presented along with a brief overview of various R&D activities.