Commissioning of the BIL Tracking Chambers for the ATLAS Muon Spectrometer

Muon tracking in the ATLAS experiment at the Large Hadron Collider is based on high-pressure drift tubes (MDT) immersed in a toroidal air-core magnetic field. We present the commissioning of 116 barrel inner large chambers that will equip the inner ring of the ATLAS muon spectrometer. The gas system, the front-end electronics, the alignment system, the temperature and magnetic field probes were installed and verified. Also the chamber response was controlled with cosmic rays and all test results were stored in a database for future reference. All chambers were certified as ready for installations and are about to be installed in these months in the ATLAS experiment.