EXTRANUCLEAR LABORATORIES WILL INVESTIGATE A DETECTOR FOR IONS IN A MASS SPECTROMETER IN WHICH IONS ARE ACCELERATED TOHIGH ENERGY AND THEN PERMITTED TO STRIKE A METAL SURFACE, WHERE THEY PRODUCE SECONDARY ELECTRONS.

EXTRANUCLEAR LABORATORIES WILL INVESTIGATE A DETECTOR FOR IONS IN A MASS SPECTROMETER IN WHICH IONS ARE ACCELERATED TOHIGH ENERGY AND THEN PERMITTED TO STRIKE A METAL SURFACE, WHERE THEY PRODUCE SECONDARY ELECTRONS. THE ELECTRONS ARE THEN ACCELERATED TO A SCINTILLATOR WHERE THEY PRODUCE PHOTONS TO ACTUATE A CLOSED PHOTOMULTIPLIER TUBE. THIS TYPEOF DETECTOR IS KNOWN AS A DALY DOORKNOB DETECTOR WHEN THE PHOTONS ARE IN THE VISIBLE REGION. THE PRESENT WORK ADDRESSES THE POSSIBILITY OF USING A SCINTILLATOR THAT PRODUCES PHOTONS IN THE FAR UV RATHER THAN THE VISIBLE SPECTRUM. IN THIS CASE, THE PHOTOMULTIPLIER NEED NOT HAVE APHOTODYNODE WITH A LOW WORK FUNCTION AND ITS ATTENDANT THERMAL EMISSION NOISE. PREVIOUS EXPERIMENTS ON UV PHOTON COUNTERS SUGGEST CERTAIN MATERIALS AS POTENTIAL SCINTILLA- TORS IN THE FAR UV. THESE WILL BE TESTED AND, IF PROMISING,BE BUILT INTO A DALY DOORKNOB CONFIGURATION. COMPARISON OF SENSITIVITY AND NOISE LEVEL OF THIS DETECTOR WITH A CONVEN- TIONAL OPEN CHANNELTRON DETECTOR WOULD BE MADE.