High-momentum final-state muons are amongst the most promising and robust signatures of physics at LHC. To exploit this potential, the ATLAS Collaboration has designed a high-resolution muon spectrometer with momentum measurement capability over a wide range of muon energies and angles. The conceptual layout of the spectrometer is based on the magnetic deflection of muon tracks in a system of three large superconducting air-core toroid magnets. In the barrel region, tracks are measured in chambers arranged in three cylindrical layers around the beam axis; the chambers are built with the Monitored Drift Tubes technology.
The Rome group in the years 2001-2004 produced 64 MDT chambers, which have been mounted in the ATLAS detector and are since then fully operational. These chambers have contributed in a substantial way to all the major ATLAS discoveries, the Higgs boson included.
