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 5 T 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 vacuum ultraviolet 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.