New ideas in CsI-based photon detectors: wire photomultipliers and protection of the photocathodes

We discuss the idea of a vacuum or gaseous photomultiplier with a CsI-coated wire photocathode. It benefits from an electric field enhanced quantum efficiency. We present a method for protecting air-sensitive photocathodes with thin dielectric film coating. Results of CsI coated with thin LiF and MgF/sub 2/ films are shown. The protection of other UV and visible photocathodes is discussed.<
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