Ion Feedback Afterpulses in ФЭУ-130 and XP2020 Photomultipliers

Intensities and time distribution spectra of ion feedback afterpulses were studied as a function of the potential differences between the photocathode and first dynodes in ФЭУ-130 photomultipliers with the aim of using this type of photomultiplier in autocorrelation delayed-coincidence spectrometers. The intensities and amplitudes of the afterpulses in an ФЭУ-130 are found to be substantially larger than those in XP2020 photomultipliers, which are usually used in delayed-coincidence spectrometers.