Study on after-pulses of FPMTs

Abstract

The small-sized Micro-Channel Plate Photomultiplier Tube (MCP-PMT), also called Fast-timing PMT (FPMT), has gained significant attention across various fields due to its single-photon detection capability and great time resolution. The after-pulses are spurious pulses occurring after the main pulse and cannot be distinguished from the true signals, which means the occurrence of the after-pulses can contribute to the noise of the FPMT. In this study, the waveforms of the FPMTs were recorded by a high-sampling-rate oscilloscope, and we measured the after-pulse characteristics of different types of FPMTs, including the time distribution and the after-pulse rate. The causes of different after-pulse groups are also analyzed. Additionally, we conducted a comparative analysis of the distinct properties of after-pulses in different types of FPMTs.