{Chub, Jordan, Chandra (Kyle helped as needed)}

Fought the flange alignment almost all day on the new turbo installation. Was able to torque the turbo isolation GV flange when one of the 32 studs failed while approaching metal-to-metal. Tomorrow we will pull the unit back and redo flange and chase thread on GV blind hole (if needed).

YMB is being pumped by turbo since this morning. Pressure is currently 1e-6 Torr. At some point we need to move aux pump cart to GV5's annulus to hog out air from known inner o-ring leak on manifold side.

[Ethan, Niko]

Went to EY in the afternoon for transmitter module maintenance. Tx shutter is working fine, OFS range is about where it was previously, laser output power is exactly where it was 6 months ago, and the AOM diffraction efficiency is doing well at 81.4%.

OFS Open Loop Transfer Function Bode plot attached below, along with the filled-out maintenance document. Rx beam alignment looks poor (see attached), we will likely have to adjust this in the near future.

Went to EX this morning for transmitter module maintenance. Tx shutter is working fine, OFS range is about where it was previously, laser output power has dropped very slightly (1.76 -> 1.73 W over 3 months), and the AOM diffraction efficiency is at 69% (not great but not needing adjustment just yet).

OFS Open Loop Transfer Function Bode plot attached below, along with the filled-out maintenance document. Rx beam alignment looks good.

Betsy had warned that earlier this morning during the venting of the vertex, a few ISIs had tripped.  She warned that perhaps they might trip again as we pump back down, and a few did.

I am recovering:

• ISI HAM4
• ISI ITMX st2
• SUS OM2
• ITMY st1, st2

From about 21:15 to 22:30UTC (2:15 to 3:30 PM Local) I had the fan running on ISCT1, and doors open (one at a time) to verify the current version of the DCC layout for H1 ISCT1.   Mostly the layout was correct.  I found one additional lens, one iris, and some beam dumps that are moved.  No changes.

C. Gray, G. Moreno, T. Sadecki, B. Weaver

Install of the new yawed septum viewport in HAM 6 went very smoothly today.  We utilized 2 of the aligment pins (3/8-16 silver plated screws with the heads lathed down to thread diameter) that Tyler made for us.  This made the installation much easier as we had something to take the weight of the 22 kg viewport assembly while installing the mounting flange screws.  The septum window accelerometer was reinstalled in the same location it was removed from.  First Contact was removed from the inner, HAM 5 side prior to installation, and the outer, HAM 6 side was removed in-chamber after installation and torquing.  The center of the viewport aperture was inspected and was deemed free from egregious amounts of particles.  

On a related note, this was the first time I had the chance to use the new modular stair system around the HEPIs and can attest that they work much better than the previous iterations of HAM chamber stairs.  

Photos to follow.

Posted are the CPS Noise Spectra Checks. The IFO is down for planned engineering. 

Closing FAMIS # 12868

    Laser Status:
    Front End Power is 32.57W (should be around 30 W)
    70W Output Power is 69.02W
    Front End Watch is GREEN
    70W Watch is GREEN

    PMC:
    It has been locked 12 days, 23 hr 57 minutes (should be days/weeks)
    Reflected power = 12.13Watts
    Transmitted power = 51.91Watts
    PowerSum = 64.04Watts.

    FSS:
    It has been locked for 3 days 2 hr and 59 min (should be days/weeks)
    TPD[V] = 3.049V (min 0.9V)

    ISS:
    The diffracted power is around 2.9%
    Last saturation event was 0 days 0 hours and 0 minutes ago (should be days/weeks)

    Possible Issues: No issues to report. Site is in Planned Engineering for vent.

Daniel, Dave:

Daniel made a h1sqz model change to add four new ISS filtermodules ( CTRL and ERR for CLF and OPO). He also made the corresponding change to the Beckhoff C1PLC4.

Between the times of 12:24 and 12:35 PDT I restarted the following:

h1sqz model

DAQ, followed quicked by h1edc

Note that h1nds3 (stand-alone EDCU) was not restarted. This system does not have the new PLC4 slow channels.

I took the opportunity to restart a stuck Slow-Controls SDF system (h1sysecatc1plc1sdf).

added 350ml toTCSX, 700ml to TCSY. 

The TCSX filter is quite green, and when I popped the filter out, I saw a green line of resudue on the tank under the area where the filter seals to the tank.  This was most obvious where the return water emptys into the filter.  The green resudue easily wiped off.  The TCSY chiller, in contrast, was not green at all, and there was no evidence of any resudue under the filter.

This is a follow up on measurements done in 51546  and modeling 50610  A few weeks ago I did a longer set of squeezing measurements using the full range of the CLF demod phase shifter and the sign flip in the CLF servo board.  I repeated the measurement for the nominal 100 count SRCL offset which we use to minimize the optical spring, and an offset of -100, which corresponds to roughly a 100 to 120 nm detunign of the SRC (extrapolating from 51592).  The first attachment shows these measurements with the correlated noise subtracted, you can see that we are reaching nearly .

The second and 3rd attachments shows the same data, I've taken the median in several frequency bands (avoiding lines) for each demod phase and used an MCMC fit for a model that includes loss, nonlinear gain, phase noise, and the ratio of the OMC 3MHz semi-major and semi-minor axsis.  I used Daniel's expression here to model the realtionship between squeezing angle and demod phase.  The last attachment is a collection of the corner plots for all of these fits.

The next two plots show the fit parmeters plotted as a function of frequency for the nominal SRCL offset  and with SRC detuning.  In these plots the blue stars show the median of the posterior dsitribution, while the triangles show the 16th and 84th percentile of the parmeter.  I've divided out the budgeted effecincy based on the known losses so that we should be able to compare these plots to similar plots produced by Lee's code.  I've plotted the normalized nonlinear interaction strength x, which is not frqeuency dependent, because there is some frequency dependence in the fit results, because of degeneracy with phase noise. 

The code used to make these plots is available here, inlcuding a script which will run the measurement by slowly varying the CLF demod phase and SRCL offset, and sqz_as_phase_rotates,py, the main script which produces the plots.

Needed some internet so I'm here to monitor YBM pump down while catching up on personal volunteer work. Will valve QDP80 back out and log when I leave.