User name Bogdan/jpchen
Log entry time 11:09:56 on August13,2001
Entry number 70712
Followups:
keyword=Switched left gas Cherenkov #9 PMT. HVs set back for all channle for left Gas Cherenkov.Bogdan finished switch PMT for left Gas Cherenkov #9. All HVs set back on.
Adjusted #9 HV (ch#8) to be 2600 V (was 2800 V before switching), dark current
is 495 uA.
Bogdan: I put fresh good PMT from recent delivery, new HV divider. CO2 flow
was 30 l/h, put switch on high flow - 200 l/h. Need to return back after 48 hours.
Adjusted single ph.e. amplitude to 100-120 mV -> HV = 2600 V. Initial counting
rate was 3.7 kHz, but dropping fast.
FIGURE 1
FIGURE 2
