Photomultiplier tube base for high pulsed anode currents

Abstract The stability of photomultiplier tube (PMT) gain for signal conditions of high pulsed anode currents requires a PMT base circuit capable of maintaining constant voltage to the last few dynodes for the pulse duration. For the experimental conditions at the Los Alamos Meson Physics Facility (LAMPF) with a macropulse duration of 500 μs at 120 Hz, conventional base circuits do not meet stability requirements. The new base circuit uses high voltage transistors to furnish pulse currents to the last four dynodes of the PMT from a single capacitor source which is recharged during the period between macropulses.