MDT Chambers Research Articles

A high-precision X-ray tomograph for quality control of the ATLAS Muon Monitored Drift Tube Chambers

A dedicated X-ray tomograph has been developed at CERN to control the required wire placement accuracy of better than 20 μm of the 1200 Monitored Drift Tube Chambers which make up most of the precision chamber part of the ATLAS Muon Spectrometer. The tomograph allows the chamber wire positions to be measured with a 2 μm statistical and 2 μm systematic uncertainty over the full chamber cross-section of 2.2×0.6 m 2. Consistent chamber production quality over the 4-year construction phase is ensured with a ∼15% sampling rate. Measurements of about 70 of the 650 MDT chambers so far produced have been essential in assessing the validity and consistency of the various construction procedures.

The muon spectrometer of the ATLAS experiment

The muon spectrometer of the ATLAS experiment at CERN LHC is reviewed. Background conditions, design performance, Level-1 trigger scheme and the different tracking detectors are presented. Results from recent tests on the performance of the MDT chambers and of the alignment system are discussed.

Large precision muon detector for ATLAS

Abstract The ATLAS muon spectrometer is designed to exploit the full physics discovery potential at the Large Hadron Collider in a stand-alone mode. The precision muon detector is made of monitored drift tubes with tracking precision better than 50 μm to measure the muon track sagitta in the toroidal magnetic field. A world-wide intensive construction work of the ATLAS muon detector is under way. We report the precision muon detector mass production experience, including the R&D results on the long tube operation stability and the impact on the momentum resolution due to wire sag. The quality control data in mass production are presented. Cosmic ray test results show that the MDT chambers have tracking efficiency close to 100% and single wire resolution is better than 80 μm .

The monitored drift tube (MDT) chambers for the muon precision tracking in the ATLAS spectrometer

The ATLAS muon spectrometer has been designed to exploit the very wide range of the physics potentialities at LHC. One of the very ambitious goal to be achieved is the precise measurement of the muon tracks, up to very high momenta, at luminosity L≥ 10 34 cm −2s −1. To attain the goal, a system of three large superconducting air core toroid magnets, instrumented with very high precision tracking chambers, has been adopted. The high precision of the MDT tracking chambers is achieved through a rigorous assembly procedure in which a very precise jig is used. The various aspects of the system and the MDT chamber assembly procedure are described in the following.