Measurement of the electron transmission rate of the gating foil for the TPC of the ILC experiment

Abstract We have developed a gating foil for the time projection chamberenvisaged as a central tracker for the international linear colliderexperiment. It has a structure similarto the Gas Electron Multiplier(GEM) with a higher optical aperture ratio and functions as an ion gate without gas amplification. The transmission rate for electrons was measured in a counting mode for a wide range of the voltages applied across the foil using an 55 Fe source and a laser in the absence of a magnetic field. The blocking power of the foil against positive ions was estimated from the electron transmissions.