Log entry time 03:22:52 on June 26, 2010

Entry number 328273

Here's a quick HOWTO for the VDC TDC calibration:

Take data:
  white spectrum
  1M+ single arm triggers if possible
  only VDC and trigger scintillators necessary

Replay & analyze:
  Log in as adaq
  cd ~/apex/vdc
  source setenv.sh
  analyzer
   .L replay_vdccalib.C+
   replay_vdccalib("L", 1095)   // 1095 is the run number
   ...... 
   .L calibVDCtdc.C+
   calibVDCtdc("L","vdccalib_1095.root")
   ......

Finish:
4 large panels pop up. Inspect the plots carefully. Red vertical lines
indicate properly fitted offsets, blue lines, estimated values due to
failed fits. Red trianges indicate peak(s) found, which should
correspond to the drift time peak. If satisfied, copy data from output
files (tdcoff_L_u1.txt etc.) into VDC database file under "TDC Offset
Values", overwriting old values.