After three more iterations today of accelerating then stopping GV12's VFD-driven motor following 0 - 300 rpm, stop, wait (hours) 0 - 300 rpm, stop, wait etc. pattern, the MEDM screen position indication finally transitioned from RED (CLOSED) to YELLOW (not CLOSED, not OPEN). 

I had noted initially that, when fully closed, the ball screw is recessed below the pulley nut(?) about 10 inches.  Today, when the CLOSED limit switch transitioned states, I noted that the ball screw was flush with the pulley nut.  Hmmmm...if this is by design, then this could be helpful in the future when assessing the degree of closure for these valves.  On related note, when fully open, the ball screw measured 37 7/16" above the pulley nut.  The hand marked measurement (written in ink pen in the vicinity) for this left by whoever inititally commissioned this valve back in 1997/8 was 37 9/16".  I wonder if this discrepancy is due to casual measuring, or, would I have achieved 37 9/16" today had the valve been driven to the OPEN limit switch at full speed? 

   This morning the last of the in-house vacuum system was removed from Mid-y and End-X. This completes the removal of the in-house vacuum system from across the site. Closing WP #7440. 

   Shutdown and removed the chamber side dust monitor (VEA-2) from End-X.  

Jeff is transitioning the LVEA to laser hazard.

our old (gentoo 2.6.35) DAQ trend writer h1tw1 died at 01:45 this morning. There were messages on the console and the cpu was locked up. The console messages did not quite look like the 208.5 day bug, but on restart it forced an fsck because it had been running in excess of 246 days, so this may be the cause.

We have the replacement unit for h1tw1 on hand, FRS10834 covers its installation.

h1nds0 was in fact NFS mouting h1tw1, I changed this to h1tw0. If anyone needs raw minute trends for this morning, please switch your NFS to h1nds0.

I adjusted the temperature at E X after the chamber was closed up and the purge air compressors were turned off.
The temperature at both end stations is set at 65 degrees F. 

Gabriele, Georgia, Sheila, Craig

After the model changes yesterday, and after relocking the mode cleaner after today's work inside the PSL, we worked on a script to measure the spot positions in the IMC.  Jenne had started a script for this, but since we needed to make the model changes we edited it today.  

We are currently running the measurement, the script is at userapps/isc/common/scripts/decoup/a2l_min_IMC.py

It runs 6 dither lines on pit and yaw for MC1, MC2, and MC3.  

Operated GV12's VFD motor in the OPEN stroke three times throughout the day today following 0-300 rpm, stop, wait a few hours, repeat process.

In addition to the work logged by Keita here and here, and the cooling work logged by Jeff here, we performed the following:

-Physically installed the 70W amplifier external shutter.  The shutter has not been connected electrically yet, we will do that once we can turn the laser and PSL Control Box OFF.  Since the shutter is not connected electrically, the shutter flag was temporarily removed (as the shutter's default position is CLOSED).  Once the shutter has been connected electrically and proper operation confirmed, the shutter flag will be reinstalled.  See attached pictures.

-Removed the power supply cable for the existing IO_AB_PD3, as the connector is needed for the new power cable for the large-area PD that will be installed as the new IO_AB_PD3.

-As part of the bullseye PD installation, we had to swap the HR mirror that directs a pick-off beam into the PD for the 70W amp power watchdog with a beamsplitter.  As a result of this, we re-calibrated the watchdog PD for proper watchdog operation.

-Had Bubba look at the Laser Room door.  Over the last several weeks the door has become difficult to move; it is likely we need to have the manufacturer take a look at it.

(Kyle R, Gerardo M)

Removed o-ring valve from housing for NEG pump PT-191, replaced it with a new metal seal valve.  Aux cart will be left running overnight pumping on the new volume only, will continue working on it tomorrow.

We reinstalled the bull's eye detector on PSL.

Caveat: When the power on the detector was too much, three segments of the outer ring railed at ADC (i.e. -32k counts), but the center segment only reached -30k or so (attached), it's not like the power on the central segment was smaller than the others, it was quite contrary. Maybe there was some analog problem going on.

We installed an ND filter to reduce the power, plus RG850 to make sure that no pump light reaches bull's eye.

Right now the center segment is at -23k counts, ring segments are about 10k each. Calibration of the sensor will be worked on by Thomas and Georgia.

As was reported in  alog 42311, last week ALS path power on the ISCT1 was found to be much lower than it used to. Suspicion was that the power was throttled on the PSL table intentionally, which turned out to be the case. We went to the PSL room today to increase the power.

Before we started working, ALS path power on the PSL table was about 180mW. Rick adjusted HWP right after the PMC to minimize the rejected beam on the polarizer, and the power in the ALS path increased to ~900mW.

Main path power after EOM was 39.5W and H1:PSL-PWR_PMC_TRANS_OUTPUT was displaying 42.7 W (and H1:PSL-PWR_PMC_REFL_OUTPUT 18.9W, which is pretty bad BTW) , which we can use to calibrate things later. For now PSL rotator calibration as well as H1:PSL-EOM_A_DC_POWERMON calibration are both totally bogus.

After this we've done many things including but not limited to bull's eye reinstallation, and somehow the alignment into PMC got even worse (right now PMC transmission is only 20W). Jason says we need to realign into PMC.

Pumped out the gas out of the 3 NEG pump housing on top of the OMC tube, PT-191, PT-192 and PT-193.  There was no issues pumping down the volume on all 3 NEG pumps.  All 3 NEG pumps were valved into the main volume, PT-193 was first then PT-192, and PT-191 was last.

Unfortunately soon after the aux cart was decoupled from the PT-191 the pressure started raising (NEG was isolated from the aux cart via both of its valves), an indication of a leak somewhere.  We decided to isolate PT-191 from the rest of the vacuum system until we can resolve that issue, PT-192 and PT-193 remain valved in.

Replaced pump had been in operation since Oct. 2002.

Spun turbo up this afternoon, backed by QDP80. Pressure currently at 2.6e-5 Torr.

No difficulty unlocking except for the access restrictions from ISC tables and laser assemblies.  Signs have been changed; please be mindful of the suspended parts.

Running Range-of-Motion tests; will report shortly.