Thin Gap Chamber upgrade for SLHC: Position resolution in a test beam

The position resolution of two small TGC with different readout strip pitch was measured by 10 GeV/c pion in PS-T9 test beam in November 2007 at CERN. The position resolutions ranging between 50 and 150 μm have been obtained up to the largest incident angle of muons in the so-called Small-Wheel region. The worsening of the resolution as a function of angle is expected in this type of wire-chamber detectors, due to the elongation of the avalanche along the wire, however the results achieved satisfy the needs for the SLHC upgrade.