A straw transition radiation tracker for the LHC

The role and the performance of an integrated straw tracker and transition radiation detector (TRT), as proposed for the ATLAS experiment at the future Large Hadron Collider (LHC), have been extensively investigated by the RD6 collaboration, with Monte Carlo simulations, test beam studies of prototype detectors and laboratory tests of the various elements. Here, we summarize the properties of the straw tubes as detecting elements and we present test beam results which demonstrate the tracking and particle identification capabilities of the detector.