Reports until 18:29, Thursday 27 July 2017
H1 SUS
jeffrey.kissel@LIGO.ORG - posted 18:29, Thursday 27 July 2017 - last comment - 13:35, Thursday 03 August 2017(37830)
SUS Triples Checked for Rubbing with Top-to-Top Mass TFs
J. Kissel

I'm behind on my documentation as I slow process all the data that I'm collecting these days. 
This aLOG is to document that on this past Tuesday (2017-07-25) I took standard top-to-top mass transfer functions for the Triple SUS (BS, HLTS, and HSTS; 10 SUS in total), as I've done for the QUADs (see LHO aLOG 37689 and associated comments).

I saw no evidence of rubbing during the act of measurement, but I'd like to confirm with a thorough comparison. As such, I'll post comparisons against previous measurements, other suspensions, and the appropriate model in due time.

This leaves: 3 doubles, 9 singles.

Data is stored and committed here:
/ligo/svncommon/SusSVN/sus/trunk/BSFM/H1/BS/SAGM1/Data/
2017-07-25_1501_H1SUSBS_M1_WhiteNoise_L_0p01to50Hz.xml
2017-07-25_1501_H1SUSBS_M1_WhiteNoise_P_0p01to50Hz.xml
2017-07-25_1501_H1SUSBS_M1_WhiteNoise_R_0p01to50Hz.xml
2017-07-25_1501_H1SUSBS_M1_WhiteNoise_T_0p01to50Hz.xml
2017-07-25_1501_H1SUSBS_M1_WhiteNoise_V_0p01to50Hz.xml
2017-07-25_1501_H1SUSBS_M1_WhiteNoise_Y_0p01to50Hz.xml

/ligo/svncommon/SusSVN/sus/trunk/HLTS/H1/PR3/SAGM1/Data/
2017-07-25_1507_H1SUSPR3_WhiteNoise_L_0p01to50Hz.xml
2017-07-25_1507_H1SUSPR3_WhiteNoise_P_0p01to50Hz.xml
2017-07-25_1507_H1SUSPR3_WhiteNoise_R_0p01to50Hz.xml
2017-07-25_1507_H1SUSPR3_WhiteNoise_T_0p01to50Hz.xml
2017-07-25_1507_H1SUSPR3_WhiteNoise_V_0p01to50Hz.xml
2017-07-25_1507_H1SUSPR3_WhiteNoise_Y_0p01to50Hz.xml

/ligo/svncommon/SusSVN/sus/trunk/HLTS/H1/SR3/SAGM1/Data/
2017-07-25_H1SUSSR3_M1_WhiteNoise_L_0p01to50Hz.xml
2017-07-25_H1SUSSR3_M1_WhiteNoise_P_0p01to50Hz.xml
2017-07-25_H1SUSSR3_M1_WhiteNoise_R_0p01to50Hz.xml
2017-07-25_H1SUSSR3_M1_WhiteNoise_T_0p01to50Hz.xml
2017-07-25_H1SUSSR3_M1_WhiteNoise_V_0p01to50Hz.xml
2017-07-25_H1SUSSR3_M1_WhiteNoise_Y_0p01to50Hz.xml

/ligo/svncommon/SusSVN/sus/trunk/HSTS/H1/
PR2/SAGM1/Data/2017-07-25_1607_H1SUSPR2_M1_WhiteNoise_L_0p01to50Hz.xml
PR2/SAGM1/Data/2017-07-25_1607_H1SUSPR2_M1_WhiteNoise_P_0p01to50Hz.xml
PR2/SAGM1/Data/2017-07-25_1607_H1SUSPR2_M1_WhiteNoise_R_0p01to50Hz.xml
PR2/SAGM1/Data/2017-07-25_1607_H1SUSPR2_M1_WhiteNoise_T_0p01to50Hz.xml
PR2/SAGM1/Data/2017-07-25_1607_H1SUSPR2_M1_WhiteNoise_V_0p01to50Hz.xml
PR2/SAGM1/Data/2017-07-25_1607_H1SUSPR2_M1_WhiteNoise_Y_0p01to50Hz.xml

PRM/SAGM1/Data/2017-07-25_1607_H1SUSPRM_M1_WhiteNoise_L_0p03to50Hz.xml
PRM/SAGM1/Data/2017-07-25_1607_H1SUSPRM_M1_WhiteNoise_P_0p01to50Hz.xml
PRM/SAGM1/Data/2017-07-25_1607_H1SUSPRM_M1_WhiteNoise_R_0p01to50Hz.xml
PRM/SAGM1/Data/2017-07-25_1607_H1SUSPRM_M1_WhiteNoise_T_0p01to50Hz.xml
PRM/SAGM1/Data/2017-07-25_1607_H1SUSPRM_M1_WhiteNoise_V_0p01to50Hz.xml
PRM/SAGM1/Data/2017-07-25_1607_H1SUSPRM_M1_WhiteNoise_Y_0p01to50Hz.xml

SR2/SAGM1/Data/2017-07-25_1715_H1SUSSR2_M1_WhiteNoise_L_0p01to50Hz.xml
SR2/SAGM1/Data/2017-07-25_1715_H1SUSSR2_M1_WhiteNoise_P_0p01to50Hz.xml
SR2/SAGM1/Data/2017-07-25_1715_H1SUSSR2_M1_WhiteNoise_R_0p01to50Hz.xml
SR2/SAGM1/Data/2017-07-25_1715_H1SUSSR2_M1_WhiteNoise_T_0p01to50Hz.xml
SR2/SAGM1/Data/2017-07-25_1715_H1SUSSR2_M1_WhiteNoise_V_0p01to50Hz.xml
SR2/SAGM1/Data/2017-07-25_1715_H1SUSSR2_M1_WhiteNoise_Y_0p01to50Hz.xml

SRM/SAGM1/Data/2017-07-25_1814_H1SUSSRM_M1_WhiteNoise_L_0p01to50Hz.xml
SRM/SAGM1/Data/2017-07-25_1814_H1SUSSRM_M1_WhiteNoise_P_0p01to50Hz.xml
SRM/SAGM1/Data/2017-07-25_1814_H1SUSSRM_M1_WhiteNoise_R_0p01to50Hz.xml
SRM/SAGM1/Data/2017-07-25_1814_H1SUSSRM_M1_WhiteNoise_T_0p01to50Hz.xml
SRM/SAGM1/Data/2017-07-25_1814_H1SUSSRM_M1_WhiteNoise_V_0p01to50Hz.xml
SRM/SAGM1/Data/2017-07-25_1814_H1SUSSRM_M1_WhiteNoise_Y_0p01to50Hz.xml
Comments related to this report
jeffrey.kissel@LIGO.ORG - 18:33, Thursday 27 July 2017 (37831)
More detailed plots of BS, compared against previous measurements and model. We see perfect agreement with model and previous measurement, so this SUS is definitely clear of rubbing.
Non-image files attached to this comment
jeffrey.kissel@LIGO.ORG - 13:28, Friday 28 July 2017 (37853)
More detailed plots if PR3 and SR3. Both are clear of rubbing.

The new measurements agree with old measurements of the same suspension, the model, and other suspensions of its type.

PR3's L2L transfer function shows "extra" unmodeled resonances that were not there before, but they line up directly with the Y modes. This is likely that, during the measurement the Y modes got rung up, and the power is so large that it surpasses the balance the of the sensors, so they're not subtracted well. I can confirm that these frequencies are incoherent with the excitation, and we've seen such inconsequential cross coupling before. Nothing about which to be alarmed.
Non-image files attached to this comment
jeffrey.kissel@LIGO.ORG - 16:24, Monday 31 July 2017 (37912)
More detailed plots of PRM, SRM, and SR2 compared against previous measurements and model. We see good agreement with model and previous measurement, so these SUS are clear of rubbing.

There is a subtle drop in response scale factor for all of these suspensions (and in retrospect it's seen on the other SUS types too), and I suspect this is a result of the OSEMs LEDs slowly loosing current over the series of measurements, see attached 4 year trends.
Images attached to this comment
Non-image files attached to this comment
jeffrey.kissel@LIGO.ORG - 16:34, Monday 31 July 2017 (37914)
While PR2 shows all resonances are in the right place, there is a suspicious drop in scale for the L and Y DOFs with respect to prior measurements. However, this is the first measurement where we've measured the response with the nominal alignment offsets needed to run the IFO (!!).
These DOFs (L and Y) have the LF and RT OSEM sensor / actuators in common (see E1100109 for top mass OSEM layout), so I checked the OSEM sensors, an indeed the LF OSEM sensor is on the very edge of its range at ~1400 [ct] out of 32000 (or 15000 [ct] if it were perfectly centered).

I'll confirm that the suspension is free and OK tomorrow by retaking the measurements at a variety of alignment offsets. I really do suspect we're OK, and the measurement is just pushing the OSEM flag past its "closed light" voltage and the excitation is becoming non-linear, therefore reducing the linear response.

I attach the transfer function data and a 4 year trend of the LF and RT OSEM values to show that we've been operating like this for years, and there's been no significan change after the Jul 6th EQ.
Images attached to this comment
Non-image files attached to this comment
jeffrey.kissel@LIGO.ORG - 13:35, Thursday 03 August 2017 (37981)
I'd forgotten to post about the OMCS data I took on 2017-07-25 as well. 

The data lives here: 
/ligo/svncommon/SusSVN/sus/trunk/OMCS/H1/OMC/SAGM1/Data/
    2017-07-25_1812_H1SUSOMC_M1_WhiteNoise_L_0p02to50Hz.xml
    2017-07-25_1812_H1SUSOMC_M1_WhiteNoise_P_0p02to50Hz.xml
    2017-07-25_1812_H1SUSOMC_M1_WhiteNoise_R_0p02to50Hz.xml
    2017-07-25_1812_H1SUSOMC_M1_WhiteNoise_T_0p02to50Hz.xml
    2017-07-25_1812_H1SUSOMC_M1_WhiteNoise_V_0p02to50Hz.xml
    2017-07-25_1812_H1SUSOMC_M1_WhiteNoise_Y_0p02to50Hz.xml

Detailed plots now attached, and they show that OMC is clear of rubbing; the data looks as it has for past few years, and what difference we see between LHO and LLO are the lower-stage Pitch modes which are arbitrarily influence by ISC electronics cabling running down the chain (as we see for the reaction masses on the QUADs).
Non-image files attached to this comment