Precision tracking with small-strip Thin Gap Chamber (sTGC): from Test Beam to ATLAS NSW Upgrade

The forthcoming luminosity upgrade of LHC to super - LHC (sLHC) will increase the e xpected background rate in the forward region of the ATLAS Muon Spectrometer by approximately a factor of five. Some of the present Muon Spectrometer components will fail to cope with these high rates and will have to be replaced. A development of the Th in Gap Chambers (TGC) has been tested during the last four years. The results of these tests , presented here, showed that the small strip Thin Gap Chambers (sTGC) provide a fast trigger and high precision muon tracking under sLHC conditions. In 2012, sTGC technology has been accepted as a part of the New Small Wheel (NSW).