User name V. Sulkosky
Log entry time 20:16:07 on October19,2007
Entry number 209218
Followups:
- 209219 10/19/07 20:23 V. Sulkosky S2 ADC Channels
- 209266 10/21/07 17:36 V. Sulkosky Light leaks Check S2 (HRSR)
The HVs for the right HRS S2 scintillator were adjusted to align the
ADC spectra. Figure 1 shows the spectra before the HV adjustment for
run # 20027. Figure 2 shows the spectra after HV adjustment for run
# 20056.
A couples notes:
1) The S2-1R, S2-2R and S2-4R PMTs are close to the edge of their HV
range between -2400 V and -2450 V. Eventually these PMTs will need
to be replaced.
2) After adjusting the HVs, the rate from S2-1L, S2-1R, S2-5L was
1-1.5 kHz. The rate from S2-5R was also higher at 700 Hz. When the
detector hut lights were turned off the rates for all four PMTs
dropped to comparable levels (300 to 350 Hz) with the other 8 S2
PMTs, indicating a light leak.
FIGURE 1
FIGURE 2
