Momentum Resolution Studies for a large TPC-Based Central Tracker

This note describes a study on the momentum resolution of the TPC-based central tracker design which will be included in the ECFA/DESY conceptual design report (CDR) for the proposed DESY 500 GeV electron-positron linear collider. The study found it to be likely that the central tracker could achieve a momentum resolution of approximately 10^{-4} (GeV/c)^{-1}, particularly if a layer of silicon microstrip detectors were to be added just inside the TPC.