Speaker
Dr
Valerie GAUTARD
(CEA-SACLAY)
Description
The muon spectrometer of the ATLAS experiment aims at reconstructing very high
energy muon tracks (up to 1 TeV) with a transverse momentum resolution better than
10 %. For this purpose a resolution of 50 micrometer on the sagitta of tracks has to
be achieved. Each muon track is measured with three wire chambers stations placed
inside an air core toroid magnet (the chambers seat around the interaction point in
three layers and 16 sectors). In particular, the contribution to the sagitta due to
the limited knowledge of the chamber positions and deformations should not exceed 30
micrometer. Therefore a network of optical survey monitors, called alignment system
is being installed.
This network is made up of six different alignment types: i) the IN-PLANE alignment
measures chamber internal deformation; the PRAXIAL system is composed of two parts:
ii) the PROXIMITY part which gives the position of one chamber with respect to the
neighbouring one and iii) the AXIAL part controls the “saloon door” effect of
chambers relative position within a layer, iv) the PROJECTIVE system gives the
chamber position within a triplet; v) the REFERENCE system is used to link a sector
of chambers to the neighbouring sector; vi) the CCC system connects large chambers
to small chambers since the lasts are not individually aligned.
In this paper we will describe the software managing the complete system from
calibration of individual sensors to implementation of the whole system including
some test beam results.
Primary author
Dr
Valerie GAUTARD
(CEA-SACLAY)
