[Corey, TJ, Betsy, Koji]

RESOLVED ISSUES:
- The issue of the suspension TF was resolved by adjusting one of the OMC EQ stop holders [LHO ALOG 28900]
- The sign-flip issue of the DCPD signals has been explained by the accoustic noise of the OMC [LHO ALOG 28901]

PROGRESS:
- The lock nuts of the upper mass EQ stops were fastened (by fingers)
- The black glass panels of the OMC shroud were restored. We checked the input/reflection apertures to be well aligned against the beams.
- The OMCT steering mirror was restored to the optical mount.

- The alignment of the WFS path was reviewed. It was found that the path is still well aligned. Just the WFS QPDs were manually aligned by the mounts with picomotors.

- We attached the viewport simulator on the flange to check the alignment of the in-air paths. The AS AIR path was very well centered on the viewport without touching. The OMCR path is about 50% towards East (-Y) from the center of the viewport. We could not find the OMCT spot no matter how we flash the OMC. This could be just the beam was too dim, or was blocked by the shroud. We'll investigate this on Monday again.

TO DO:

- Continue to work on the OMCT path alignment. This requires ~10W IMC input. Try to find a dim flashes. Use a CCD camera on a tripod to find the spot around the viewport cover.
- We want to check the calibration between AS_C QPD SUM, the incident power on OM1, and the incident power on the OMC breadboard.
- Other ISC items function check (picos, beam diverters, fast shutter - see Rich's comment below, etc)
- Ground loop check
- Other SUS/SEI exit check

Purge air has been mysteriously throttled to a "trickle" going into HAM6 (no longer my battle)

Looking at the voltage of the AS port trigger PD as seen by the shutter controller, we have just under 2V at 50W input. The maximum threshold is 2V, so this won't work. The QPD chassis of AS_C has serial number S1301506 indicating an R23 of 26.7K in the sum output. This needs to be reduced to 12.4K, or we have to reduce the modulation depth of the 45MHz before we reach 50W.

The current configuration of the BSC-ISI's does not use any high gain ST2 RX/RY isolation loops because we dont have a blend filter design that rolls off fast enough at low frequency to avoid injecting GS-13 noise back into the X/Y dofs. However, above 1 hz the suspension point motion is dominated by ST2 RX/RY motion. One way we can improve this is by using relatively low gain AC coupled loops on ST2 RX/RY. With RichM's help I've tested this some on a couple ISI's and it seems to work, but there are trade-offs. First attached plot shows the improvement in ETMX longitudinal motion I've managed to get. Green and brown are the ground for both measurements, pink traces are RY loops on, light blues is off. In the 2-10 hz band I can get about a factor of about 2.5 reduction (I've seen up to ~5) , but at about 1 hz the motion is worse by about a factor of 2. Not spectacular, and I'm not sure that the improvement at a few hz is worth the loss at 1 hz. I've looked at the oplev (second plot, pink is on, light blues is off) and the oplev doesn't seem to see a substation difference at 1 hz.

One reason to do this would be to speed recovery after a lock loss. The ISI RX/RY loops get rung up by the impulse from the suspension, and it seems plausible that the ISI would settle down quicker is the RX/RY loops had more gain.

The designs for the ETMs RX/RY loops are included in the attached pdf. The lugfs are around 1 hz, uugfs are around 10-20 hz, phase margins are around 40-50 degrees. Higher gain loops didn't seem to provide much more isolation, but made the motion around 1hz worse.

21:00 - 23:00 UTC

21:05 UTC Joe and Chris done working on wind fence at end X
21:13 UTC Jeff realigning ITMY, misaligning ITMX for crew at HAM6
22:03 UTC Robert and Ansel at end Y. Do not change ISI from damped to isolated.
22:16 UTC Jason done in optics lab

J. Kissel
ECR E1500045
FRS 6014
WP 6051

While attempting to quickly install the ITM updates in between the HAM6 work, I found that ITM models would not compile as is. Errors in the compilation process reminded me that their upgrade would not be as simple as copying and pasting from the ETMs (thanks for all the great error messages, Rolf! They're, sincerely, very useful nowadays). This complexity a result of the differing BIO control of the ESD stage drivers, so the BIO block as a whole cannot be the same. 

Further, I discovered that I forgot to switch the EUL2OSEM matrix on the FOUROSEM_DAMPED_STAGE_MASTER_WITH_DAMP_MODE.mdl library part that controls the L2 stage of both the QUAD_MASTER.mdl (for ETMs) and QUAD_ITM_MASTER.mdl (for ITMs) from a regular matrix to a ramping matrix.

This means that the ITMs are ready for install, and the ETMs need a re-install to gather this bug fix. I'll coordinate with the HAM6 install/repair team and with the CDS crew. 

I've since made the model changes, and all QUADs now successfully compile, but all QUADs will need to have these models installed and rebooted. 

For future reference, changes have been made to 
/opt/rtcds/userapps/release/sus/common/models/
QUAD_MASTER.mdl                  << Modified the BIO block to use the new Individually Controlled 
                                    PUM library block, arranged connections from BIO to L2 
                                    blocks accordingly
QUAD_ITM_MASTER.mdl              << (same as above) Modified the BIO block to use the new 
                                    Individually Controlled PUM library block, arranged 
                                    connections from BIO to L2 blocks accordingly
STATE_BIO_MASTER.mdl             << Created new library block for individual control of PUM driver
FOUROSEM_DAMPED_STAGE_MASTER_WITH_DAMP_MODE.mdl     << Modified COILOUTF bank to accept individual control
                                                       and switched EUL2OSEM matrix from static to ramping

and they've been committed to the userapps svn repo. I attach screenshots of all the relevant parts that have been modified, named after the simulink blocks, respectively.

Removed temporary extension cord for GV15 AIP329 and replaced it with new extension cord, work done under WP 6060, and this closes FRS ticket 5950.

State of H1:  OMC work continues, progress on PDs

Activities:

• 19:08 - Krishna - back from LVEA
• 19:08 - Michael - back from LVEA
• 19:50 - Krishna - back from LVEA
• 19:50 - Michael - back from LVEA
• 19:57 - Kyle - EY - temperature readings
• 20:11 - Koji, Corey, TJ - back to LVEA OMC
• 20:30 - Robert - EY
• 20:38 - Richard - LVEA OMC
• 20:39 - Kyle - back from EY
• 20:55 - Jason - Optics Lab
• 20:58 - JeffK - ITMX and ITMY model restarts

~1330 hrs. local 

Opened exhaust check-valve bypass-valve, opened LLCV bypass-valve 1/2 turn -> LN2 @ exhaust in 45 seconds -> Restored valves to as found configuration. 

Next CP3 overfill to be Monday, August 8th.

Chris B. and Ryan F. reported that during the hardware injections in ER9, the H1:CAL-PINJ_TRANSIENT_OUT channel did not fall below 1e-200 counts until about 1 hour after the last BBH injection. He also said this was not observed in O1. One needs to consider the following two points:

First, one cannot directly compare the TRANSIENT_OUT channel from O1 and ER9 because they had fundamentally different units. In O1, the channel had units of strain, in ER9, it had units of counts. In ER9, the strain time series has passed through the inverse actuation filters.

Second, if one instead looks at the HARDWARE_OUT channel in O1 (after the IAF during O1), any impulse response to the transient signal ending would be completely masked by the continuous wave signal that has been added to the HARDWARE_IN time series. Thus it doesn't make sense to have a 1e-200 threshold on the HARDWARE_OUT channel during O1.

To invstigate the ER9 IAF, I have separately computed the impulse response of the different filters. The biggest impulse response comes from the f^2 filter module because it has high gain at high frequencies (see first attachment). This is to be expected.

I also compare the impulse response of the IAF used in O1 and the IAF used during ER9 (second and third figures, respectively). The O1 actually has a bigger impulse response and longer duration. I would surmise from this that any oscillations are actually worse in O1 than they are now.

Conclusion:
From this investigation, there is nothing to suggest that the ER9 IAF are worse than O1. In fact, the new IAF provide improved signal fidelity and the impulse response suggests that the new IAF is actually better than the O1 version.

J. Kissel, K. Arai, C. Gray, T. Shaffer, B. Weaver

After a great deal of inspection of the top mass, where I thought the OMCS was locked last night (see LHO aLOG 28883), the in-vacuum team list above identified that an earthquake stop on the bottom mass / breadboard / M2 stage was rubbing slightly. Once this EQ stop was backed off, all DOFs of the suspensions top to top mass dynamics returned to the expected results akin to the former OMC. Nice work team!

Attached are screenshots of drawings of the OMC with the offending EQ stop highlighted with a red square, as well as the transfer functions themselves. On the transfer function plots, 
BLACK shows the former OMC reference measurements, 
BLUE is yesterday's measurement with the EQ stop rubbing, and 
RED is the current OMC suspended, free of rubbing.

Templates for today's measurements live here:
/ligo/svbcommon/SusSVN/sus/trunk/OMCS/H1/OMC/SAGM1/Data
2016-08-05_1909_H1SUSOMC_WhiteNoise_L_0p2to50Hz.xml
2016-08-05_1909_H1SUSOMC_WhiteNoise_P_0p2to50Hz.xml
2016-08-05_1909_H1SUSOMC_WhiteNoise_R_0p2to50Hz.xml
2016-08-05_1909_H1SUSOMC_WhiteNoise_T_0p2to50Hz.xml
2016-08-05_1909_H1SUSOMC_WhiteNoise_V_0p2to50Hz.xml
2016-08-05_1909_H1SUSOMC_WhiteNoise_Y_0p2to50Hz.xml

Notes: 
- Because I wanted yesterday's measurements in the template as a reference, and we were in rush, I did not head my own advice and use the templates from 28736. Just keep this in mind. At least, this time, I'd paid attention to the frequency resolution and made it the same 0.02 Hz BW across all DOF's templates, but I did not add in the low-frequency boost. Again, one can stil get the information needed out of these templates, but they could be better.
- I only took a few averages. This is the luxury of having reference transfer functions and suspensions with very repeatable dynamics: we know immediately -- even after one average -- that if the resonance frequencies, zero frequencies, and their respective Qs line up with the reference then the suspension is healthy. More averages will just reduce the incoherent noise on the TF at all frequencies, and since these measurements are in air, we expect a good deal of incoherent noise at all frequencies anyway.

State of H1: OMC PD electroincs pulled for testing - issues are ongoing, OMC suspension issues are resolved

Activities: all times UTC

• 15:24 - Koji - LVEA - OMC - electronics check at HAM6, back
• 16:12 - Kyle - EY - check on bake
• 16:25 - Betsy - LVEA - getting batteries
• 16:31 - Koji - optics lab then LVEA OMC - OMC alignment
• 16:51 - Christina - EX - cleaning
• 16:55 - Betsy - LVEA OMC
• 16:59 - Richard - LVEA OMC - checking out electronics
• 17:07 - Richard - out of LVEA - has pulled the chassis for PDs and has it in EE
• 17:10 - Robert - EY - may cause a trip - cleared with JimW
• 17:21 - Bubba - EX - wind fence
• 17:29 - Richard, Fil - LVEA OMC - chassis back out to the floor
• 17:37 - Corey - LVEA OMC
• 17:42 - Micheal,Krishna - LVEA vertex - seismometer
• 17:52 - Richard - back from LVEA, Fil still in LVEA
• 17:55 - Bubba - back from EX
• 17:58 - Jason - Optics Lab - inspecting TCS mirrors
• 18:00 - Gerardo - MX - WP6060
• 18:00 - TJ - LVEA OMC
• 18:05 - Christina - leaving EX
• 18:10 - Chandra - EY then EX - viewport cover inspection
• 18:54 - Gerardo - back  from MX
• 18:54 - Stefan - LVEA OMC
• 18:58 - Fil, Corey, TJ, Koji, Stefan - out of the LVEA

Dust:

• 17:40 - EX dust - yellow alarm
• 18:02 - EX dust - red alarm

Alignment:

• 18:51 - HAM5 ISI Trip, now recovered

J. Warner

Jim has put gathered some data on the wind fence. Check out SEI aLOG 1050.

Chandra, Gerardo, Patrick

Degassed the two nude ion gauges in corner station - PT170 & PT180 on BSC 7 & BCS 8. First degassed PT170 (700degC for 3 min. according to manual). We monitored the adjacent PT120 CC gauge, where pressure barely rose (8.48e-9 Torr to 8.52e-9 Torr). Pressures at the two ion gauges rose significantly and caused a verbal alarm at the operator console; pressures spiked to ~2e-7 Torr and then settled down to base pressures.

Note:  degassing draws ~ 70 W and thus caused PT120 pirani to flat line and CC to read bogus pressure reading during degassing. This happened during PT180 degas, but not with PT170. 

We also noticed that PT140A periodically flat lines - linked to PT110 (?).

The OMC scan was performed last night after the chamber was covered. While the scan showed noimnal resonant features of the slightly misaligned cavity, I saw negative trips of the DCPD outputs (both) when the photocurrent is of the order of ~0.1mA. 

The attched plot shows the refl QPD sum (CH1), scanned PZT Voltage (CH2), and the DCPD A/B outputs (CH3/4). The output of the DCPDs are usually positve, while they trip to negative occasionally when the cavity hit the major resonances. The positive voltage segments show nice resonant features when they are plotted in a logscale.

The refl QPD sum shows that the light was nicely absorbed by (transmitted through) the OMC. So it seems it is not optical.

I quickly checked the power supply condition of the field rack and confirmed that the related chassis are on.

We want to figure out this feature by the time we close the dorrs next week as the DCPD preamps are located in HAM6.

The HV power cable for the Y2-8 ion pump has been repaired. The damaged section was cut off, and the cable was spliced together. Cable was tested with the HI-POT tester to 5KV.

J. Kissel, E. Goetz

We've taken another DARMOLG TF and PCAL2 DARM transfer function in order to see if / how the SRC Detuning Optical (Anti-)Spring is changing from lock-stretch to lock-stretch. The bad (but not necessarily unexpected) news: it looks like the optical (anti-)spring frequency is moving around. One can tell by looking at the lowest frequency data points in the .pdf attachments. The model has a spring frequency of 9.381 Hz and both measurements are divided by it to form the residuals on the right column of subplots. Note also that Kiwamu and Craig's more sophisticated parametrization for the optical spring (which includes some Q between in the anti-spring poles, see LHO aLOG 28274) is not yet included. Jul 1 data points are ~ +15% discrepant in magnitude, where as Jul 09 data points are ~ +25%. 

More thoughts on this (what to do about it, how to track it, tests to try and control / reduce it) after the weekend. 

The pre-processed sensing function has been attached here, such that whomever gets to it first, can reproduce the fit using Craig's code from LHO aLOG 28274.

Data sets live here:
${CalSVN}/trunk/Runs/PreER9/H1/Measurements/DARMOLGTFs/2016-07-09_H1_DARM_OLGTF_4to1200Hz_SRCTuned.xml
${CalSVN}/trunk/Runs/PreER9/H1/Measurements/PCAL/2016-07-09_H1_PCAL2DARMTF_4to1200Hz_SRCTuned.xml