A time projection chamber with GEM-based readout

Abstract For the International Large Detector concept at the planned International Linear Collider, the use of time projection chambers(TPC) with micro-pattern gas detectorreadout as the main tracking detector is investigated. In this paper, results from a prototype TPC, placed in a 1 T solenoidal field and read out with three independent Gas Electron Multiplier(GEM) based readout modules, are reported. The TPC was exposed to a 6 GeV electron beam at the DESYII synchrotron. The efficiency for reconstructing hits, the measurement of the drift velocity, the space point resolution and the control of field inhomogeneities are presented.