The barrel-inner-large tracking chambers for the ATLAS muon spectrometer: Ready for installation

We describe the commissioning and performance tests of 116 high pressure drift tube chambers, MDT, built to equip the inner ring of the Muon Barrel Spectrometer of the ATLAS experiment at the Large Hadron Collider. After assembly and test in the home laboratories, the chambers were transported at CERN, equipped with the final version of the front-end electronics, alignment system, temperature and magnetic field probes, slow controls for a complete system-test of all detectors. The uniformity of response of the drift tubes and the tracking performance of the chambers were measured with cosmic rays before installation in the experiment. A summary of the commissioning procedure and of the results of the performance tests is presented.