This morning Travis and I went into BSC10 (EY), swung back the ACB to gain space around the ETMY QUAD structure, and started the disassembly of the QUAD - removing QTY 4 VA's, cross braces, Sleeve wedges, and started on some of the sleeve fasteners.  We then did a fit-check to see if we could get the install arm elevator into place without having to also swing back the TMS.  We didn't get the sleeve removed but it looks like we'll be able to get the elevator in the spaces around the QUAD structure without having to pull the TMS back.  We'll try next ~Tues-Wed and see how far we get.

(Note, swinging back the TMS involves a lengthy process of adding support brackets and equipment to the TMS lower table section, loosening some of the suspended cable sections, stopping up the upper mass, then pulling it back for a few extra inches of clearance.  Resetting it all after the maneuver is complete will result in a many day period of realignment of the TMS.)

The TCS Y chiller that has a leaky seal (SN# 0110193301120813) has been replaced with the spare (SN# 0127640801150617). New quick connect fittings were used as the old ones had been cross-threaded. I used the old settings from the original chiller on the spare chiller (attached here, couldn't find a document containing them). No leaks or water level dropping could be detected after several hours of running, will recheck tomorrow.

Measured dew point of EY purge air for about 12 minutes this morning, with no demand (closed off metal valve to get flow through pressure relief valve). DP crept down to -25.3degC. Then found a "switching failure alarm" on at the control panel (visual only - no sound). I reset and re-measured DP. Quickly dropped to -22degC in several seconds. The two drying towers appear to be cycling between regenerating and drying.

Compressors are running between three and four units with current flow. Output pressure is 0.5-0.7 psi. Soft cover was on BSC door, but arm is in chamber.

Not really too important for the IFO maybe but as a test/proof of concept, this DOF was addressed as it was easier.

After a few iterations of the HEPI  Y to RZ IPSALIGN factor (H1:HPI-ETMX_IPSALIGN_3_2) the value that reduced the YAW seen on the Oplev YAW sufficiently was determined.

As I showed in 40106, driving the HEPI platform in X or Y produced Yaw seen on the optical lever.  Including the Y to RZ factor above in the control scheme reduced the yaw seen on the optical lever about a factor of 10.  The attached plot shows the same channels as in log 40106.  As X is not being driven, there is no OpLev Length to Angle correction.  This time period shows 2 measurement with different IPS_ALIGN factors: -0.007 & -0.0055.  This was just to convince me that the process was effective.  This really needs to be done for the in-line drive, ETMX X and ETMY Y drive.  These effects are pretty small and the ASC has managed to deal with the YAW induced when a long lock stretch drive HEPI 100s of um.  Still if the ASC doesn't have to deal with this, it should be a good thing.

Once I figure out how to a priori compute this with just a couple measurements, I'll do this for the in-line drive which will be a bit more involved given the OpLev Len2Ang correction.  Notice too, the RX_OUT16 (middle left plot); I'll look at other sensors to see if the horizontal drive is actually producing real tilt.  It may not be real unless our local sensors on HEPI are being fooled just like the YAW loop is as I showed in 40106.

Pressure is stabilizing at CP4 after isolating it and valving in a small ion pump. Working with CDS team to set/adjust pressure alarms.

Wondering was these perturbations are in corner station pump down. Peaks from Wed. morning and step down Thursday morning.

- Jenne, Cheryl, Keita

Jenne and I confirmed that the beam from the PSL did not require any adjustments. The REFL beam was present on IOT2L and the beam was on the REFL camera.   On IOT21L we adjusted the alignment of the REFL path to clear the iris/HWP/CalciteWedge combination of optics and cleanly dump beams before the 2" steering mirror to the REFL diode, and after those adjustments we restored the beam to the REFL camera.  Because we're not using WFS at this time, the beams onto WFSA and WFSB were not adjusted.

Searching for the good beam found yesterday, it was found again today, however, as we walked the PZT and MC1 the power dropped steadily.  I went to HAM3 West door and took a few pictures with the IR camera, and saw that there was a large beam on the beam dump post that is in from of MC2 Trans.  We confirmed this beam as the reflection from MC3, and drove MC3 and MC2 alignments to ensure that there are no IMC mirror reflections coming back to HAM3.

Talked to Keita, plan is to scan the PZT to look for a beam(s) on MC2 Trans QPD, because we calculated the angle needed to move the beams on MC2 Trans (600urad) and the PZT should have the range to put the real beam on the QPD.

Jenne is running two AWGGUIs on ZOTWS1 that has a sticky note on the left monitor saying "In Use" to control the PZT overnight.  The PSL power is at 2.7W (requested 4W).  Alignment of the IMC mirrors should not be changed until tomorrow morning (end of test).

The PZT scanning will be complete well before 6:30AM, so HAM2 HEPI locking and scaffolding work should proceed as planned.

Keita noticed just now that there is a readback error on AS B 36 whitening gain.  We should fix this before we start needing AS WFS.

On Tuesday, Dave and I drove to EX to restart the seismic computer and most of the rack components to see if we could get the .085 hz feature that RichM found in December. Sadly, turning on then off again hasn't fixed the problem. I have been able to narrow down the source, I think. In the asds we took before, the feature seemed biggest in the RX/RY loops, so I started by turning those off. This made the feature go away in the X/Y dofs ( or maybe it just got smaller than the background?), it also made the peak disappear in all sensors other that the T240s. I think this shows that the peak is coming from something in the Z1/2/3 (local) T240 signal chain. To dig in a little further I collected an hours worth data with the ISI in this configuration ( ST2 damping only, ST1 RX/RY/Z isolation loops off, X/Y ISI sensor correction off, HEPI Z sensor correction off) and looked at the coherent subtraction between the 3 local Z T240 signals, as shown in the attached figure. The first plot shows the asds of the 3 local channels, Z1 & Z2 are similar at .085hz, but Z3 has a small bump. The second plot shows the result coherently subtracting each of the channels from one another. The fact that the .085hz goes away for subtractions that don't include Z3 makes me thing that there is something going on with the corner 3 sensor. I don't have time tonight to see if this extends to the horizontal dofs on that corner, but I think I want to try power cycling the T240 chassis again at EX.

Covering the latter part of Patrick's shift from 22-23utc (2-3pmPST).  Here are activities:

• 22:07 Tranfer functions complete for ITMy (Kissel)
• 22:09  swapping in new TCS chiller (was a back up) to replace leaky one & then checking for leaks in LVEA (Greg)
• 22:11 LVEA is now Laser HAZARD (Bubba transitioned)
• 22:14 MY (maybe also EY) to make measurements) (Bubba, & Mark)
• 22:22 IMC work (Jenne at IOT2L & Cheryl at PSL)
• 22:22 Going to Squeezer Rack (Nutsinee)
• 22:33 EY is now Laser SAFE (Evan)
• 22:44 PCal Group back (Travis, Darkhan, Evan, Rick)

23:00----OPS Meeting Time

End Of Ops DAY Shift

and there may be a minor amount of yaw coupling.

The attached 25 minute time series shows a +-200000nm drives in X & Y on ETMX. This offset into the ISO loop is ramped in for 120 seconds.  The upper left plot shows the ISO_RZ output keeping the computed RZ_LOCATIONMON at zero.  The lower right plot X_LOCATIONMON is used to calculate the Length to angle coupling on the Optical Lever output:

OpticP(Y)[urad] = OplevP(Y)[urad] - LengthDrive[nm] * Len2Pit(Yaw)CC[mrad/m] * 1e-9[m/nm] * 1e3[urad/mrad];    Len2Pit(Yaw)CC from E1200836: 20.89 (11.9)mrad/m

So in the two upper right plots, the Pitch and Yaw expected to be seen on the Oplev due to the X motion are, shown in blue and subtracted from the raw Oplev output (red) giving the residual in black.  We believe the HEPI calculations for position are very good and our loops hold things at those positions.  With that assumption, we'd expect most of the signal seen on the OPLEV is from the drive.  As the residual during the X drive is small (<20%,) maybe this suggests the coefficients in E1200836 are not too far off.

So, for ETMX, certainly most of Pitch and Yaw seen on the optical lever when driving X is from the Cross-coupling effect.  But there appears to be some actual optic YAW from these HEPI translation.  There is no a priori cross-coupling from Y motion on ETMX as the Optic shears across the optic normal.   The YAW seen during the Y translation is twice as large as during the X motion suggesting that even with our loops closed, we are still getting some YAW at the optic..

This is pretty small and obviously the ASC loops are managing with this and when do we ever translate the optic 200um?  Oh, yes, for tidal relief...

TITLE: 01/11 Day Shift: 16:00-00:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Planned Engineering
LOG:

Corey covering from 22:00 UTC to 23:00 UTC
Operator meeting at 23:00 UTC (no coverage)

15:07 UTC Chris to LVEA to retrieve clean and bake items for Betsy
15:56 UTC Mark and Tyler to LVEA to retrieve equipment for Rick. Craning equipment over beam tube.
16:28 UTC Mark and Tyler done
16:45 UTC Bubba to end Y
16:48 UTC Gerardo to LVEA to check on aux pump cart by HAM5
16:55 UTC Ed to LVEA to stage cable for WP 7279
17:09 UTC Gerardo back
17:16 UTC Mark and Tyler to end Y to retrieve equipment through outer rollup door
17:16 UTC Jeff B. starting WP 7280
17:18 UTC Ed and Filiberto starting WP 7279
17:39 UTC Bubba back from end Y
18:13 UTC Bubba to LVEA to look for legs for scaffolding
18:19 UTC Bubba back
18:20 UTC Marc to LVEA to look for Filiberto
18:26 UTC Mark and Tyler done at end Y
18:42 UTC Chandra to mid Y and end Y to check on things
19:07 UTC Ed and Filiberto done pulling cables. Ed making pigtails. Cables need to be terminated. Filiberto starting connection of TCS laser to safety system on mezzanine.
19:08 UTC Travis to optics lab to get IR viewer then cleaning area to get headsets.
19:12 UTC Gerardo to LVEA to turn off aux pump cart by HAM5
19:18 UTC Jeff B. out of LVEA
19:19 UTC Travis back
Gerardo back
19:32 UTC Cheryl to IOT2L to install beam block
19:43 UTC Yannick to LVEA to take pictures of PEM devices
19:56 UTC Betsy to LVEA to drop off wipes
19:59 UTC Jenne to join Cheryl at IOT2L table
20:04 UTC Betsy back
20:09 UTC Yannick back
20:45 UTC Jenne and Cheryl back
20:52 UTC Jeff K. taking transfer function on ITMY reaction chain
20:55 UTC Rick, Travis, Evan, Darkhan to end Y for PCAL
21:00 UTC Vent meeting in CR
21:03 UTC PCAL group transitioning end Y to laser hazard
21:37 UTC Ed and Filiberto to LVEA to continue cable pulling
21:54 UTC Bubba transitioning LVEA to laser hazard

No planned intervention on PSL
cdsfs0 restart scheduled for ~ 6am next Tuesday
PSL locked/tagged out after laser damage found on IOT2L table panel yesterday
Leak checking done
Plans to install ion pump on CP7
Vent meeting scheduled for next Tuesday at 9:30 am (due to Monday holiday)
Investigation of slightly strange ITMY reaction mass transfer function
HEPI pump maintenance continues
end Y HVAC changes to mitigate temperature increase
Scaffolding to be installed between HAM2 and IO table over HEPI piers tomorrow
Bubba has ALS and PCAL lasers locked/tagged out

[Cheryl, Jenne]

We added a few beam dumps to IOT2L, just in case the IMC Refl beam gets moved far enough that it's not going to the designed mirrors and beam dumps.  There is one large dump behind the top periscope on the refl path, and one each behind the 2 high power dumps that dump most of the power. 

Following up on alog 40014 with reported issues on MO and RO signal chain. Looked at possible grounding issues. Tested cable SUS_ITMY-8 at satellite box and found pin 2 shorted to chamber ground. To eliminate the air-side cable, we tested directly at the feedthru. Same results, pin 2 shorted to ground. The AA/AI/Coil driver driver electronics were also power cycled.

(Bubba, Gerardo)

Removed and replaced the rubber stopper size 1 from HAM6 north door annulus, replace it with a size 0.  Pumped down on system with an aux-cart and pressure as of 19:00 utc was at 8.0x10^-6 torr, aux cart will remain on until tomorrow.

J. Kissel

Wrapping up the core optic suspensions standard rubbing check top-to-top transfer functions after pump down, I've measured the main (M0) and reaction (R0) chains of H1SUSITMX and H1SUSITMY. 
ITMX looks great and free of rubbing, no "ifs," "ands," or "buts".
ITMY shows poor response / low coherence in both main and reaction chain vertical.

Conclusion: (albiet a weak conclusion) I suspect something is awry with the ITMY M0 (LF RT) / R0 (LF RT) OSEM signal chain, with a slight preference toward it being a drive problem. I *hope* that it's an external-to-chamber problem.  More discussion below. 

Attached are the results.

Discussion of ITMY:
- Start with the comparison between previous measurements, allquads_2018-01-05_H1SUSITMY_All_Phase3b_ALL_ZOOMED_TFs.pdf, and flip to pages 3, 9, and  10 for the M0 V to V, R0 V to V, and R0 R to R. 
NOTES: 
    - These are particularly low coherence, and these are driven with the same excitation amplitude as ITMX. 
    - I tried to drive harder, in case the templates were tuned for some other configuration, and it saturates the DAC, so the templates *are* well tuned. 
    - As per normal, I was in the top coil driver state 1, i.e. that with the low-pass OFF, and therefore the most DAC range.
    - Also, there are features in the R0 R to R transfer function at 1.11 1.70 2.82 4.52 5.90 (+/- 0.01) Hz that don't correspond to any other DOF's resonances for either chain.

- Next look at the individual measurements detailed TF analysis, 2018-01-05_1944_H1SUSITMY_R0_ALL_TFs.pdf. Pg 3 and 4 are repeats of what you've seen, but 
NOTES: 
    - on pg 7 (L to V), pg 9 (R to V), pg 11 (P to V) which show the "expected" or "interesting" cross-coupling between the vertical DOF and others, one sees pretty good reciprocity. I.e. we see that what features and frequency response shape are seen in the V to ? TF are also seen in the reciprocal ? to V transfer function. This is evidence toward the sensors/electronics being a problem and not the suspension's dynamics. Admittedly, the P to V and V to P TFs look the least alike. These TFs *have* changed from the previous at-vacuum measurement of this suspension (see 2017-07-20_2358_H1SUSITMY_R0_ALL_TFs.pdf from LHO aLOG 37848), but it's unclear if one could claim that one was "better" or "more right" than the other.
    - on pg 15 (V to LF RT) and 16 (R to LF RT), one can see that both sensors are showing the same response to the drive (as was true in 2017-07-20 data set as well), but it just looks over all weaker. This implies that it's a *drive* electronics problem, not a *sensor* electronics problem.

A final note: other than
    - Aligning / Rebalancing the Reaction Chain,
    - Installing BRDs & NMBDs on the Main Chain, and
    - Resolving all in-vac cable grounding issues
we did comparatively little to this suspension.

Following all these clues, I was perusing aLOGs to see if I could find any hanging chads regarding the cable grounding issues, and found LHO aLOG 39675, but 
    (a) Those cables in question for ITMY were for R0's (F1 F2 F3 SD) and PUM (UL LL UR LR) signal chains, *not* for those involved with these transfer functions, namely the M0 (LF RT) / R0 (LF RT) signal chain, and
    (b) Richard assures me that *every* grounding issue in that aLOG was resolved (confirmed quickly by Besty in passing by LHO aLOG 39749)

As a final test, I ran the R0 V to V transfer function with all DOF's damping loops CLOSED -- see 2018-01-05_2214_H1SUSITMY_R0_V_Damped_WhiteNoise_0p01to50Hz.png for the results (BLACK is the 2017-12-20 data set, MAGENTA is the latest 2018-01-05 undamped data set shown the analysis .pdfs, and RED is the damped data set).
The only major difference (besides the -- surprisingly in-effective -- reduction of the primary vertical modes), is that the extra 1.11 1.70 2.82 4.52 5.90 (+/- 0.01) Hz features are reduced to the in-air 2017-12-20 level.

Measurement Templates:
/ligo/svncommon/SusSVN/sus/trunk/QUAD/H1/
ITMX/SAGM0/Data/2018-01-05_1828_H1SUSITMX_M0_WhiteNoise_L_0p01to50Hz.xml
ITMX/SAGM0/Data/2018-01-05_1828_H1SUSITMX_M0_WhiteNoise_P_0p01to50Hz.xml
ITMX/SAGM0/Data/2018-01-05_1828_H1SUSITMX_M0_WhiteNoise_R_0p01to50Hz.xml
ITMX/SAGM0/Data/2018-01-05_1828_H1SUSITMX_M0_WhiteNoise_T_0p01to50Hz.xml
ITMX/SAGM0/Data/2018-01-05_1828_H1SUSITMX_M0_WhiteNoise_V_0p01to50Hz.xml
ITMX/SAGM0/Data/2018-01-05_1828_H1SUSITMX_M0_WhiteNoise_Y_0p01to50Hz.xml

ITMX/SAGR0/Data/2018-01-05_1923_H1SUSITMX_R0_WhiteNoise_L_0p01to50Hz.xml
ITMX/SAGR0/Data/2018-01-05_1923_H1SUSITMX_R0_WhiteNoise_P_0p01to50Hz.xml
ITMX/SAGR0/Data/2018-01-05_1923_H1SUSITMX_R0_WhiteNoise_R_0p01to50Hz.xml
ITMX/SAGR0/Data/2018-01-05_1923_H1SUSITMX_R0_WhiteNoise_T_0p01to50Hz.xml
ITMX/SAGR0/Data/2018-01-05_1923_H1SUSITMX_R0_WhiteNoise_V_0p01to50Hz.xml
ITMX/SAGR0/Data/2018-01-05_1923_H1SUSITMX_R0_WhiteNoise_Y_0p01to50Hz.xml

ITMY/SAGM0/Data/2018-01-05_1828_H1SUSITMY_M0_Mono_WhiteNoise_L_0p01to50Hz.xml
ITMY/SAGM0/Data/2018-01-05_1828_H1SUSITMY_M0_Mono_WhiteNoise_P_0p01to50Hz.xml
ITMY/SAGM0/Data/2018-01-05_1828_H1SUSITMY_M0_Mono_WhiteNoise_R_0p01to50Hz.xml
ITMY/SAGM0/Data/2018-01-05_1828_H1SUSITMY_M0_Mono_WhiteNoise_T_0p01to50Hz.xml
ITMY/SAGM0/Data/2018-01-05_1828_H1SUSITMY_M0_Mono_WhiteNoise_V_0p01to50Hz.xml
ITMY/SAGM0/Data/2018-01-05_1828_H1SUSITMY_M0_Mono_WhiteNoise_Y_0p01to50Hz.xml

ITMY/SAGR0/Data/2018-01-05_1944_H1SUSITMY_R0_L_WhiteNoise_0p01to50Hz.xml
ITMY/SAGR0/Data/2018-01-05_1944_H1SUSITMY_R0_P_WhiteNoise_0p01to50Hz.xml
ITMY/SAGR0/Data/2018-01-05_1944_H1SUSITMY_R0_R_WhiteNoise_0p01to50Hz.xml
ITMY/SAGR0/Data/2018-01-05_1944_H1SUSITMY_R0_T_WhiteNoise_0p01to50Hz.xml
ITMY/SAGR0/Data/2018-01-05_1944_H1SUSITMY_R0_V_WhiteNoise_0p01to50Hz.xml
ITMY/SAGR0/Data/2018-01-05_1944_H1SUSITMY_R0_Y_WhiteNoise_0p01to50Hz.xml
ITMY/SAGR0/Data/2018-01-05_2214_H1SUSITMY_R0_V_Damped_WhiteNoise_0p01to50Hz.xml