The current innermost
stations of the ATLAS endcap muon tracking system must be
upgraded to retain the good precision tracking and trigger
capabilities in the high background environment expected
with the upcoming luminosity increase of the LHC. Large area
small-strip Thin Gap Chamber (sTGC) up to 2 m
2
in
size and totalling an active area each of 1200 m
2
will be employed for fast and precise
triggering.
In particular,
the precision reconstruction of tracks
requires a spatial resolution of about 100 μm
to allow
the Level-1 trigger
track segments to be reconstructed with an angular
resolution of approximately 1mrad.
The upgraded detector will consist of eight
layers each of Micromegas and sTGC’s detectors together
forming the ATLAS New Small Wheels. The position of each
strip must be known with an accuracy of 30 µm along the
precision coordinate and 80 µm along the beam. On such large
area detectors, the mechanical precision is a key point and
then must be controlled and monitored all along the process
of construction.
A full size sTGC quadruplet has been constructed and equipped with the first prototype of dedicated front-end electronics. The performance of the sTGC quadruplet has been evaluated in test beams, where the spatial resolution was measured. We will present results obtained from the test beams and discuss the status of the construction of the first full size Canadian sTGC quadruplet prototype.