Abstract
It was tried to obtain mass spectra in a pulse counting mode with a continuous channel electron multiplier.Two continuous channel electron multiplier were used.One of them had length of about100mm, inside diameter of1.5mm and arc of270°.The resistance was about2×108Ω. Background rate was0.2cps at an applied voltage of3.0kV, 0.04cps at2.8kV and0.002cps at2.6kV. When argon ions were injected with an accelerating voltage of1kV, counting rate attained to plateau above2.3kV, and its slope was1.2%/100V. Pulse height distribution at3.0kV showed saturation. The other, which had length of about84mm, inside diameter of1mm, arc of480°and resistance of about1.5×108Ω, was mounted on a90° Kmagnetic deflection type mass spectrometer with100mm radius of curvature. Characteristics of this multiplier were studied and mass spectra of residual gas were obtained. This multiplier had background rate of2-3cps at2.4kV. Mass spectra obtained with a12stage Cu-Be electron multiplier in the pulse counting mode were also investigated.
