Quick Test of PMTs

Pulses of a Hamamatsu R5600 miniature PMT, a Hamamatsu R3809U MCP, and an Amperex XP2020UR PMT are shown in Fig. 7.30. 

The different amplitude of the pulses is the result of the different gain of the detectors (please note the different input voltage range of the oscilloscope). The different slopes are mainly a result of the different load resistance. 

Another way to increase the dynamic range is to reduee the pulse repetition rate. The downside of this solution is the inerease of pile-up distortion or acquisition time. 

It should be noted that filter fluoreseenee ean eause a signal-dependent background that is almost indistinguishable from the baekground caused by afterpulsing. Therefore, if background is a problem, the optieal system should also be 

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