D. Hosken, G. Grabeel, T. Vo

Today we wanted get the CO2X laser table in a position to run the closed system overnight.  We've taken some extensive precautions using redundant beam dumps along the laser path to make sure that we don't have stray beams and that the main laser beam does not get into the vacuum system via the periscope.

Beam dump locations:
- After the output beamsplitter
- Secondary beam dump after the final steering mirror
- A shield between the second iris and the first periscope mirror

The rotation stage was power-cycled to see if we could reproduce the errors that M. Heintze saw last week but we couldn't get the same behavior.  I also forced the Motor Warning label to be "FALSE".  We've left the rotation stage close to minimum power with about 2.2 Watts going through after the polarizers so we can monitor the beam power down stream with an on-table power meter that should be reading ~.199 Volts (working but not yet calibrated).  We expect it to go up and down a bit because of the temperature fluctuations and we left PZT/Chiller loop open.  The jumper for the interlock for the rotation stage is removed so that no one in the control room can rotate the HWP via EPICS.


We've left the HEPA and the lights off at 6:00 PM PT,  The table is locked and we've tagged out the keys and left them in the control room box with our phone numbers attached.

ISS PD adjustments:
We removed the covers and beam dump to let light onto the ISS PDs.  We also translated the PDs back ~2-3 mm back and fine-tuned the alignment onto the center of the PDS.

Temperature Sensors: 
The temperature sensors were not working very well at first.  There were only 2/6 working which turned into 1/6 as we were trying to troubleshoot.  Turns out that the problem was due to a loose connection at the feedthrough, once we tightened the connector screws, everything worked pretty well.  We'll be monitoring these temperatures quite closely during the overnight observation because it'll give us a first-look indication if anything is wrong.

H1-TCS-C_CO2_X_TEMPERATURESENSOR1 = AOM
H1-TCS-C_CO2_X_TEMPERATURESENSOR2 = PLUMBING MANIFOLD
H1-TCS-C_CO2_X_TEMPERATURESENSOR3 = AOM DRIVER
H1-TCS-C_CO2_X_TEMPERATURESENSOR4 = WATERCOOLED BEAM DUMP
H1-TCS-C_CO2_X_TEMPERATURESENSOR5 = RF DRIVER