10.02 See attachment 1 for overnight EPICS log of TUDA2.CG5
      Downstream flange secured by four bolts
      Current pressure 1.07Torr - rate of increase ~0.2 Torr/5h

11.30 TUDA chamber pumped down to ~800mbar
      Downstream flange bolts removed - no change in pressure observed
      N2 bottle connected to TUDA vent valve - to vent and (hopefully)
      exceed atmospheric pressure forcing downstream flange to move open
      Pressure measured using MKS Baratron 1000Torr gauge

      Result - pressure increased from 800 to ~1000mbar in ~45s
      TUDA chamber pressure did not noticably exceed atmospheric
      pressure and there was no obvious movement of downstream flange.
      Gas could be felt escaping from sides of downstream flange.

      Conclude - contact with downstream flange O-ring failed at, or near,
      atmospheric pressure - this prevented buildup in excess of atmospheric
      pressure

11.50 Installed:

      preamp services (+/-15V preamp power, +/- preamp test inputs) - 10-way IDC
      ribbon cables

      detector HT - SMC/BNC cabling

      preamp signals - 34-way IDC twist-n-flat ribbon cables

      preamp thermocouple attached to an S2-1 preamplifier

15.00 Time to 250mTorr ~14m
      Time from 250mTorr to 4.75E-5Torr ~45m
      See attachment 2

16.04 FTS RS44 set point +5.5 deg C

16.21 FTS RS44 temperature +5.6 deg C

17.12 TUDA2.PNG5 8.2E-06Torr
      FTS RS44 temperature +5.8 deg C
      Preamp thermocouple +8 deg C

17.13 +/-15V preamp power ON

17.18 Preamp thermocouple +14 deg C
      TUDA2.PNG5 8.0E-06Torr

17.23 Preamp thermocouple +14 deg C
      TUDA2.PNG5 7.9E-06Torr

17.28 Preamp thermocouple +15 deg C
      TUDA2.PNG5 7.7E-06Torr

17.43 Preamp thermocouple +15 deg C
      TUDA2.PNG5 7.0E-06Torr

CAEN SY403 HV mainframe

      Channel HT Detector Bias  I_L
                           (V) (uA)

          1    1   S2-1   -130  -0.03
          2    2   S2-2   -130  -0.06
          3    3   W      -250  -0.02
          4    4   PD      -30  -0.03

      Low leakage currents as expected - no evidence of high resistance
      shorts

      All other channels set to 0V

+/-15V PSUs

      #1 +15V/0A -15V/0A (MSL type W preamp not installed)
      #2 +15V/1.65A -15V/0.65A (2x MSL type S2 + 1x 16ch PD preamp units)

17.58 Preamp thermocouple +13 deg C
      TUDA2.PNG5 6.3E-06Torr

18.13 Preamp thermocouple +12 deg C
      TUDA2.PNG5 5.8-06Torr

18.29 Preamp thermocouple +12 deg C
      TUDA2.PNG5 5.3-06Torr

18.32 +/-15V preamp power OFF
      FTS RS44 set point +21 deg C

18.39 Cryo gate valve closed
      Turbo off and isolated
      4x bolts securing downstream flange removed

      Repeat yesterday's leak-in test (bolts removed)