Assembly and test of the BIL tracking chambers for the ATLAS Muon spectrometer

We describe the assembly procedure and the performance tests of 62 high pressure drift tube chambers, MDT, that equip the inner ring of the Muon Barrel Spectrometer of the ATLAS experiment at the LHC. The uniformity of response of the drift tubes and the tracking performance of the chambers were measured with cosmic rays and compared with the results obtained with high momentum muons.