Performance and some characteristics of MDT chambers constructed in IHEP (Protvino) for ATLAS

IHEP (Protvino) is responsible for construction of 60000 drift tubes and their assembling into 192 Monitored Drift Tube (MDT) chambers for two outer stations of the ATLAS Muon Spectrometer end-cap. More than 45000 tubes and 114 chambers have been assembled and tested up to now. The paper reports brief introduction of the chamber design and assembling technique. Measurements results of mechanical precision and some characteristics: precision of wire location, gas leak rate, cosmic counting rate, wire resolution - are presented.