Integration and Commissioning of the ATLAS Muon Spectrometer

The ATLAS experiment at Large Hadron Collider (LHC) has a characteristic muon spectrometer with toroidal magnetic-field for the purpose of stand-alone precision tracking and momentum selective trigger. By the combination of four types of detector technologies, the pseudo-rapidity range of | η | < 2.7 is covered by tracking chambers and | η | < 2.4 by trigger chambers. The tracking system is designed to achieve momentum resolution of better than 10% up to transverse momenta of 1 TeV. Based on the matrix-coincidence logic, the trigger system generates level-1 trigger signal and sends it to global DAQ system. Up to now, most of the system has been installed into the ATLAS pit, and all the system will be completed by the end of 2007. In the mean time, detector commissioning is intensively performed with cosmic-rays. We present the results from this activity.