Pre-commissioning 8/12/09 - 8/19/09
From Hchkswiki
Water Cherenkov
Post any completed tasks and findings in HCLOG
- Check ADC cables connected to Fastbus ADC ( )
- Connect LED in one segment to AC LED pulser signal
- Program TUL for .OR. of individual PMTs (Shichijo)
- Build trigger and gate from TUL .OR. (Joerg)
- Check ADC gate timing
- Confirm all ADC signals look good on scope
- Take a few scope pictures w/emphasis on noise level
- Take data with random trigger, e.g. LED trigger:
- Plot mean and rms of pedestal distribution as function of PMT number
- Take data with single electron trigger
- Extract mean and sigma of single electron distribution and plot vs. PMT number
- Monitor Amplifier Offset stability
- Take pedestal data every day
- Check signals on Splitter
- Set scope to 5mV/div
- Set scope trigger to -5mV
- Set scope acquisition to sample (~500 events)
- Record average pulse height for signal above scope trigger
Bucking Coil Test
The following need to be working before starting this:
- HKS Dipole ready to power
- LED pulser system for the one segment with LED
- Scalers, either visual or VME
Tasks:
- With HKS Dipole at 0 A
- Measure rate on each PMT with low discriminator threshold (10 mV)
- Take one run with LED on.
- Take one run with LED trigger but LED disconnected (pedestal run)
- Power HKS Dipole to 1065 A
- Measure rate on each PMT with low discriminator threshold (10 mV)
- Take one run with LED on.
- Take one run with LED trigger but LED disconnected (pedestal run)
- With HKS Dipole at 1065 A, repeat above measurement for a sequence of bucking coil currents: 0.5 A, 1.0 A, 1.5 A, 2.0 A, 2.5 A, 3.0 A
- Finish data with 2 more runs, Ibc=0 A & Ihks=1065 A, and Ibc=0 A & Ihks=0 A
- Analyze data and plot for each PMT rate normalized to Ihks=0.
- Determine region of maximum recovery.
- If necessary redo BC current scan with finer steps in region of interest.