The HEPI trends script was broken this morning when I launched it from the weeklies screen. This was caused by the changes to the EX channel names from the switch over to Beckhoff at that station. I updated the channels to my best guess but it's a little hard to say because the new overview doesn't seem to give a good map compared to the old overview. 

Today, Betsy and I prepped the ETMx Quad for removal of the lower structure tomorrow.  We swung back ACB, locked down all optics and masses, and disconnected all cables and wire segment necessary for removal of the lower structure.  We are in good shape for extraction from chamber tomorrow morning.

Following the installation of the improved TEC controller for the SHG, we started tuning the loop.

Figure 1: A single pole at 0Hz, a zero at 100mHz and with 10mHz selected in the ugf box. There is a fair amount of overshoot and it takes a long time to settle.

Figure 2: The zero has been moved down to 10mHz.

Figure 3: The zero has been moved down to 5mHz.

Figure 4: The zero has been moved down to 7mHz. The overshoot is about 20%. We are sticking with this value for the zero.

Figure 5: Pole at 0Hz, zero at 7mHz, another pole at 1Hz, gain of -1, ugf box set to 30mHz.

Figure 6: Response measurement at 30mHz, indicating that the ugf is around this frequency.

70W install is ongoing

Gerardo noticed this.

Kyle, Dave:

Two changes to the Vacuum cell phone alarms:

H1CDS_ROC.adl MEDM improved to show alarm levels and current value. Red border follows these alarm levels.

   Transitioned the LVEA to laser safe. Locked the ISCT6 and Squeezer cabinets. No other issues noted. 

Recall that TC1 has an offset and that it is under-representing the actual temperature it is exposed to by 6C - 10C.  

Also while at Y-mid, I closed the exhaust valve on the turbo that is pumping CP4, closed the foreline isolation valves and opened the scroll ballast/purge plug.  This allowed room air to purge, under viscous conditions, any water that may have condensed between the scroll stages since stopping the UHP N2 purge gas the other day.  I restored the configuration after a minute or two of viscous purge.  

I used the hand-held TC meter to measure the underside of CP4's vacuum vessel (1 ft. radius around vent/purge nozzle represented by TC3) and found the average temperature to be around 65C.  It would be interesting to see if we could lessen the temperature striation we are experiencing (HOT air resides at high elevations cooler air found at lower elevations) by heating the inner LN2 reservoir using the regeneration system. 

I'll be at Y-mid checking in on the CP4 bake.  I'll also "pop" in and look at the X-end and LVEA purge-air supplies.  Gerardo M. has been notified.  

I expect to be hear less than 90 minutes and will make a comment to this entry when I leave.  

Kyle has requested the high alarm level for PT243 (Y1 beam tube, adjacent to MY) be increased as it is now reading above 5.0e-08 Torr. He requests it be increased to 1.0e-07. I have done this and restarted the alarm system.

H0:VAC-MY_Y1_PT243B_PRESS_TORR   (VE gauge, MY Y1-beamtube, CC  )

current value = 5.419e-08 Torr

low alarm level = 1.000e-10  Torr

high alarm level = 1.000e-07 Torr

(Regarding camera view of CP4's bake-out control PLC display) 

I noticed that TC1 has acquired an offset as of this morning.  This TC is the closest to the heat source and, until this morning, has consistently been the "hottest" of the four displayed TCs on the PLC display.  Now, it is consistently below TC2 which is the next TC downstream in the heated air flow.  I am sure that this is the result of its extension wire connector being disturbed during the installation of the second duct heater this morning.  This extension wire connector is located very near where the work was being done and would have been in the way.  As the TC is what the PLC is using to determine the heater output, it is important that it represent the actual temperature of the air exiting the heater.  If this TC's value differs too much from TC2 or becomes "bogus" we could have a problem of the PLC overheating or underheating.  I'll keep a close eye on it over the weekend.  

Verbal alarms just reported high vacuum alarms at BSC2, BSC7, HAM6 and PT245. I can understand the ones at HAM6 and PT245 (CP4), but I'm not certain about the ones at BSC2 and BSC7. Is this due to the change in verbal alarms code [alog 41046]?

Nutsinee Terry Daniel

OPO locking:

• With the ISI no longer locked the ~1kHz acoustic peak is a factor of a few lower and the OPO locking needs correspondingly less range. The lock also looks much better now.
• We copied the guardian from the SHG and updated it for the OPO. It seems to work.
• The power coupled through the fiber was increased by a few. We get just under 6mW onto the OPO REFL diode.
• OPO REFL Photodiode DC: Unlocked 5.8mW, Locked 2.2mW. The dip in reflection therefore is 62%

Fibers:

• We tried the waveplates in the green pump path and we are able to go as low as 0.7mW for the rejected light. The adjustment was somewhat cumbersome, since both waveplates needed to be rotated simultaneously to make further improvements towards the end.
• We also tried the manual waveplates in the seed path. We were able to get the rejected light up and down by about a factor of 4. It seems difficult to do better by hand.

Translation stage:

• We were able to move the lens translation stage using the PI controller.
• We didn't try the oven translation stage since we had no feedback, if it is moving.

Next:

• We need to realign the pick-off beam towards the homodyne detector,
• and find the red/green double resonance in the OPO.

StephenA, AlenaA, NikoL, MarekS, JimW, RickS

Jim and crew completed the installation of the shield panels today.  They also adjusted the compression of the upper-right (when viewed from the ETM) flexure gap to ~0.220".

Everything seems to be installed as designed.

NikoL, MarekS, TravisS, RickS

Began assessing the centering of the Pcal beams on the input and output apertures using targets mounted to the Pcal window flanges on the A1 adapter.  We plan to continue this work in the morning, going inside the vacuum envelope to assess centering on the Pcal periscope relay mirrors. 

We plan to install the Pcal target on the ETM suspension cage for this work.