PMT rate tests
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PMT Rate Tests
Test with Reference PMT
We test the signal output of the Hamamatsu PMT assembly H10534MOD. This is based on a 10 stage tube with two outputs. The test are performed using a reference PMT assembly in a laser beam where the light output of the laser is adjusted to generate a signal in the reference PMT assembly that is similar to what is seen by the PMTs in the TOF paddle at 1550V operating voltage. One can clearly see that at 5MHz the signal is distorted as the PMT can not handle the increased current. At this point the current in the PMT increased by about 3uA from initially 253uA at 1kHz. At 2MHz the current was still at 253uA.