Gas proportional scintillation counters for the /spl mu/p-Lamb shift experiment

Large-area, 1.9-keV X-ray detectors operating in magnetic fields up to 5T are required for the /spl mu/p-Lamb shift experiment. Xenon gas proportional scintillation counters provide high detection efficiency together with good energy and timing resolutions. Three prototypes with alternative VUV-photosensors of the xenon scintillation light are explored and discussed: a CsI-coated microstrip plate either integrated within the xenon envelope or in a separate chamber in a P-10 atmosphere, and an avalanche photodiode integrated within the xenon envelope.