Georgia, Jenne, Elenna

All new offsets SDFed. I lazily accepted all the offsets without screenshots (ASC, ASCIMC, LSC, ALSEX, ALSEY, ISCEX, ISCEY, OMC). Running the script seems to have helped with our DRMI locking problems.

M. Todd, C. Cahillane

Revisiting the dataset from the March 10th, 2025  intensity noise injections that I did, Craig and I re-did a CARM pole estimate as followed in alog 65093.

Results: we estimate the CARM pole to be 0.67 +/- 0.005 Hz.

Using the Transmitted ARM RIN channels transfer function from intensity noise, we can fit a 1/f line to the low-frequency portion to estimate the CARM pole.

The plots below show some slight variation between the different channels, but all consistently around 0.67 Hz CARM pole. I have yet to examine exactly what this means for our loss estimates.

Code:

The code used to make the below plots is found:

List of Figures:

1. All together plot pdf with all transfer functions and CARM pole fits in one document
2. ISS RIN to TRX - A RIN and CARM pole fit
3. ISS RIN to TRX - B RIN and CARM pole fit
4. ISS RIN to TRY - A RIN and CARM pole fit
5. ISS RIN to TRY - B RIN and CARM pole fit

Jennie W, Sheila, Jenne D, Tony S,

Summary: PRCL loop seems to be behaving ok. Not sure why we can't lock DRMI.

We were having trouble staying locked in DRMI today so we did some open loop transfer function (OLTF) measurements of the PRCL, PRX and PRY length loops as a cross-check.

Below I include photos of the PRCL OLTF measurement where you can see there is no coherence below 20 Hz and there is a small bump in the measurement between 20 and 30 Hz.

This seemed strange so we measured PRX (state in ALIGN_IFO guardian) and PRY

Steps to lock PRY:

• I misaligned ITMX and aligned ITMY suspensions.
• Jenne D rand the PREP_FOR_PRX state in ALIG_IFO guardian
• then ran altered steps from AQUIRE_PRX state from the guardian terminal to lock us in PRY.

From the OLTF for PRX (brown trace) and PRY (red trace) we can't see any strange behaviour between 20 and 30 Hz in either state.

Finally I compared the PRCL OLTF to a measurement Ryan did a year ago, and from this (red trace) it looks as if that gain bump between 20 and 30 Hz and the rest of the TF shaping is nominal.

For completeness I include the measurement I did of MICH while PRMI was locked.

Sheila, Jennie W, Elenna,

We need to set up two DC centering loops for the PM1 suspension using the new in-vac POP_X PD.

Sheila copied over the H1:ASC-DC1_P and Y filters to the H1:ASC-DC6_P and Y filter banks after checking the shaping of these loops, and that the input and output matrices for both DOFs direct POP X  DC input -> DC6 -> PM1. We loaded the coefficients in H1:ASC model.

Elenna put in gains to match those used by DC1 and turned on the corresponding filters in the DC 6 filter banks. The inputs are off for now and we can test these later.

TITLE: 05/27 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: Ryan S
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 12mph Gusts, 5mph 3min avg
    Primary useism: 0.06 μm/s
    Secondary useism: 0.12 μm/s
SHIFT SUMMARY:
See alog from before lunch: 84591

Locking process was stopped at DRMI locking since we couldn't seem to get DRMI to lock.
But ALS locked super Quickly all day and had no issues Finding IR. 

The Baffle Dither Align Scripts we ran once in the morning.
After which we couldn't get locked past PRMI.
Jenne W. did some investigations into PRM, PRX & PRY OLTFs which Jenne W. has deemed "probably okay" in her soon to be written alog on the subject. 
After this a different Jennie Tried changing some of the gains for Mich, which did not help.
Then we re-ran the baffle scripts again.

H1 IFO STATUS: ...... Still stuggling to lock past PRMI.

LOG:   

I have checked that the input and output matrices for the REFL DC WFS centering is correct. First, I confirmed the input matrix for the DC centering by moving the RM offsets by hand in pitch and yaw and centering the beam on REFL A and B WFS. RM1 centers the beam on REFL B and RM2 centers on REFL A. This corresponds to the switch that was made in vacuum by Keita. This change is SDFed.

Next, I moved the RMs in a set offset and measured the change in the DC1 and 2 pitch and yaw inmons (scope attached). By hand I calculated the output matrix.

I calculated

pitch: [2, 1.75 ; 10.6, -32.9]

yaw: [-2, -1.5 ; 11, -28.7]

The current output matrices are

pitch: [2, 1.585 ; 9.22, -32.21]

yaw: [-2, -1.59 ; 11.03, -28.27]

which is close enough that I don't think they need to be updated.

When we engage DC1 and 2 centering, the beams converge to center as expected. However, the loop is very slow, so we may need to confirm the UGF.

TITLE: 05/27 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Planned Engineering
OUTGOING OPERATOR: Tony
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 11mph Gusts, 5mph 3min avg
    Primary useism: 0.18 μm/s
    Secondary useism: 0.19 μm/s
QUICK SUMMARY: Locking attempts are ongoing along with some SQZ homodyne alignment work. Currently aligning to lock PRMI.

Jeff, Oli

Jeff updated the damping filter gain for the RMs (84590), so I took health check transfer functions with damping loops on again (84586) and made a comparison with them vs the previous measurements.

RM1:

Data: /ligo/svncommon/SusSVN/sus/trunk/HTTS/H1/RM1/SAGM1/Data/2025-05-27_2030_H1SUSRM1_M1_WhiteNoise_{L,P,Y}_0p01to50Hz.xml, r12340

Comparison: /ligo/svncommon/SusSVN/sus/trunk/HTTS/Common/Data/allhttss_2022_vs_2025_DampingOn_wGainChange_H1SUSRM1_ALL_TFs.pdf*, r12342

RM2:

Data: /ligo/svncommon/SusSVN/sus/trunk/HTTS/H1/RM2/SAGM1/Data/2025-05-27_2045_H1SUSRM2_M1_WhiteNoise_{L,P,Y}_0p01to50Hz.xml, r12339

Comparison: /ligo/svncommon/SusSVN/sus/trunk/HTTS/Common/Data/allhttss_2022_vs_2025_DampingOn_wGainChange_H1SUSRM2_ALL_TFs.pdf*, r12342

These latest measurements are showing less gain peaking in Pitch, and almost none in Yaw. There is still gain peaking in Length, but it does look like it's a bit less than the measurements from earlier today.

* The phases for the latest (2025-05-27) measurements have been shifted by 180degrees.

Jeff, Oli

Took damped health check transfer functions for the RMs to compare how the damping has changed before vs after the vent/uninstall+reinstall/cable switching/etc.

Here are the measurements I took:

RM1:

Data: /ligo/svncommon/SusSVN/sus/trunk/HTTS/H1/RM1/SAGM1/Data/2025-05-27_1700_H1SUSRM1_M1_WhiteNoise_{L,P,Y}_0p01to50Hz.xml, r12333

Comparison: /ligo/svncommon/SusSVN/sus/trunk/HTTS/Common/Data/allhttss_2022_vs_2025_DampingOn_H1SUSRM1_ALL_TFs.pdf*, r12342

RM2:

Data: /ligo/svncommon/SusSVN/sus/trunk/HTTS/H1/RM2/SAGM1/Data/2025-05-27_1715_H1SUSRM2_M1_WhiteNoise_{L,P,Y}_0p01to50Hz.xml, r12334

Comparison: /ligo/svncommon/SusSVN/sus/trunk/HTTS/Common/Data/allhttss_2022_vs_2025_DampingOn_H1SUSRM2_ALL_TFs.pdf*, r12342

You can see for both RM1 and RM2, the resulting bumps in the old traces have now been replaced with small troughs at those same frequencies, and there are small bumps on either side. This is because the cross coupling has changed, so there is over-damping at the peak frequencies, creating gain peaking (new bumps around the peak frequencies) (84585). To get rid of this we are lowering the gain in the damping filters.

* The phases for the latest (2025-05-27) measurements have been shifted by 180degrees.

Using measured BPD values to center TMSX.
Old offset pitch -103.65326174900454 and yaw -109.59859916373702
New offset pitch -103.26627128958745 and yaw -110.61350904364517
H1:SUS-TMSX_M1_OPTICALIGN_P_OFFSET => -103.26627128958745
H1:SUS-TMSX_M1_OPTICALIGN_Y_OFFSET => -110.61350904364517
Turning off the test offsets to TMSX. (should be P -33.7, Y 30.6)
H1:SUS-TMSX_M1_TEST_P => OFF: OFFSET
H1:SUS-TMSX_M1_TEST_Y => OFF: OFFSET
TMSX dither alignment finished!

H1:SUS-TMSY_M1_TEST_P_SW1 => 8
H1:SUS-TMSY_M1_TEST_P => OFF: OFFSET
H1:SUS-TMSY_M1_TEST_Y_SW1 => 8
H1:SUS-TMSY_M1_TEST_Y => OFF: OFFSET
Using measured BPD values to center TMSY.
Old offset pitch 70.32489020986209 and yaw -271.65020191924117
New offset pitch 69.49962062863868 and yaw -270.19192585472683
H1:SUS-TMSY_M1_OPTICALIGN_P_OFFSET => 69.49962062863868
H1:SUS-TMSY_M1_OPTICALIGN_Y_OFFSET => -270.19192585472683
Turning off the test offsets to TMSY. (should be P -40.9, Y -33.1)
H1:SUS-TMSY_M1_TEST_P => OFF: OFFSET
H1:SUS-TMSY_M1_TEST_Y => OFF: OFFSET
TMSY dither alignment finished!

Using measured BPD values to center ITMY.
Old offset pitch -23.142354669728046 and yaw -19.674065180798973
New offset pitch -20.272119056234136 and yaw -18.665526580652642
H1:SUS-ITMY_M0_OPTICALIGN_P_OFFSET => -20.272119056234136
H1:SUS-ITMY_M0_OPTICALIGN_Y_OFFSET => -18.665526580652642
Turning off the test offsets to ITMY. (should be P -17.4, Y 17.9)
H1:SUS-ITMY_M0_TEST_P => OFF: OFFSET
H1:SUS-ITMY_M0_TEST_Y => OFF: OFFSET
ITMY dither alignment finished!

Using measured BPD values to center ITMX.
Old offset pitch -90.91516651598735 and yaw 110.69384598631228
New offset pitch -96.51043250715529 and yaw 109.11219915612594
H1:SUS-ITMX_M0_OPTICALIGN_P_OFFSET => -96.51043250715529
H1:SUS-ITMX_M0_OPTICALIGN_Y_OFFSET => 109.11219915612594
Turning off the test offsets to ITMX. (should be P -25.9, Y -18.5)
H1:SUS-ITMX_M0_TEST_P => OFF: OFFSET
H1:SUS-ITMX_M0_TEST_Y => OFF: OFFSET
ITMX dither alignment finished!

At the SQZ team's request, I've commented out SQZ_MANAGER from the list of nodes managed by ISC_LOCK (line 39 in ISC_LOCK.py) to allow for more free use of the Guardian for SQZ commissioning.

J. Kissel, O. Patane, E. Capote

After we dropped the RM damping loop gains (see LHO:84590), we remeasured the open loop gain transfer function (OLG TF, or just G) and loop suppression TF [ 1 / (1+G) ], in order to see / confirm that the frequency dependence in the 1-3 Hz region changes, and hopefully ''reducing'' it back to its 2022 response and regaining phase margin / reducing loop suppression magnitude.

The magnitude of the OLG TF decreased by the expect value.
The magntidue of the loop suppression also reduced back to virtually identical values.
While yes, the phase margins in the OLG TFs agree with the loop suppression, the frequency dependence of the phase of the OLG TF did *not* restore to original frequency dependence.
I again suspect the change in cross-coupling transfer functions -- namely the influence of P on the L loop and the influence of L on the P loop has changed because the underlying mechanical system has changed in this frequency region. 
Said differently, we only ever look at the on-diagonal OLG TFs. If we look, e.g. at the change in IN1 P / IN2 L (in the presence of L EXC), we might be able to get a better story. 

Oli's retaking the damped plant transfer functions [ P / (1+G) ], which will be the final metric to see if this gain adjust is ''good enough.''
Elenna will be taking before vs. after DC centering loop open loop gain transfer functions to also confirm if / whether this is ''good enough.''

Mr Todd, Georgia

We've been losing lock from DRMI a lot today and we noticed that the FIND_IR state was taking a few minutes between finding the x-arm IR and y-arm IR. We checked the ALS_DIFF guardian, and found in the stored PLL offsets (alsDiffParams.dat), the offset we were ending up (around 400) was second on the list, so we reordered the list so this is the first place the PLL goes. Now it is:

{"diffOffsets": [407.0, 3242.0, 388.0]}

Hopefully this saves valuable minutes going forward...

FAMIS 31087

I touched up PMC and FSS alignments last Wednesday (alog84512), but otherwise no major events of note.

TITLE: 05/27 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 10mph Gusts, 3mph 3min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.11 μm/s
QUICK SUMMARY:
Running the Baffle Align scripts using Camilla's alog for instructions.
Misaligned the ITMs and ETMS then ran TMS Baffle Scripts

TMSX new positions:

Using measured BPD values to center TMSX.
Old offset pitch -104.14244834736331 and yaw -109.79604786748453
New offset pitch -103.72575987167198 and yaw -110.85679978788264
Turning off the test offsets to TMSX. (should be P -33.7, Y 30.5)
TMSX dither alignment finished!

TMSY new positions:
Using measured BPD values to center TMSY.
Old offset pitch 70.15420064392093 and yaw -271.5893273344493
New offset pitch 69.75239629431661 and yaw -270.55214428728334
Turning off the test offsets to TMSY. (should be P -40.5, Y -33.6)
TMSY dither alignment finished!

Aligned ITMs and ran ITM Baffle align scripts

ITMX positions:  
Old offset pitch -101.53678089232399 and yaw 102.91810605767766
New offset pitch -101.2027177125818 and yaw 105.15047590583615
Turning off the test offsets to ITMX. (should be P -20.0, Y -14.7)
ITMX dither alignment finished!

ITMY Positions:
Using measured BPD values to center ITMY.
Old offset pitch -23.505941056968442 and yaw -20.27121873667067
New offset pitch -21.064721940378305 and yaw -19.945998085295358
ITMY dither alignment finished!

Elenna did an Initial_Alignment with out Green Camera.

Jenne D &  Camilla, Calibrated the PSL Rotation stage.

16:58 UTC Nitrogen truck Heading Down Y Arm to fill CP3

GRB-Short E572030 17:14 UTC

HAM7 ISI WD Tripped 17:14 UTC Likely due to Ken and Fil's EE work.

Locking the IFO!!!!
Manually requesting DRMI states and Pausing. So far the Highest we have reached is ENGAGE_DRMI_ASC[103]

FMCS alert : Fire pump 1 is on 17:33 UTC
FMCS alert : Fire pump 2 is on 17:44 UTC

VACUUM Alert for H1:VAC-LY_X0_PT100B_PRESS_TORR -   "That was Travis" ~ The Great Philosopher Gerardo.

2 Tours rolled through the control room and out to the overpass.

Norco N2 fill on CP1

Monthly Hanford alert test Expect Sirens at 20 UTC

Oli, Edgard, Jeff, Brian

This post is meant to give a clearer explanation of the work in [LHO:84296] and its many comments. We are trying to find a new set of gains for the M1_OSEMINF filter banks for SR3 to calibrate the OSEMs to be in agreement with the HAM5 GS13s.

To do so, we drive the HAM5 ISI in { X , Y , Z } and record the response of the relevant OSEMs between 5 to 15 Hz.  At these frequencies, the M1 stage of the suspension should start to become inertial, and the M1_DAMP / SUSPOINT response of each individual OSEM should asymptote to -1, because the OSEMs would be measuring their support point on the cage [barring internal dynamics of the cage itself].

To increase the accuracy of the calibration, we use the MATLAB model of the HLTS and use the full extent of the 5-15 Hz data instead of only the asymptotic behavior.

I post here the code used to generate these results. The code requires the new Common/MatlabTools/ExportedModels folder from the SusSVN [LHO:84458]. The detailed results of the calibrations mentioned is shown below.

_____

• We took a series of transfer functions driving HAM5_ISO_{ X , Y , Z } to measure SR3_M1_DAMP_{L,T,V,R,P,Y}. The templates for this measurement are saved in the sus SVN under [HLTS/SR3/H1/Common/Data/]
  • We can see a lot of cross-coupling in some of these transfer functions. For example, the first attachment shows SUSPOINT V to M1 R cross-coupling that ends up being consistent with sensor miscalibration. This miscalibration is also seen in the large V-to-R and R-to-V couplings in the M1 to M1 transfer functions that Oli took in [LHO:83939].
• From the measurements, we reconstruct the following transfer functions:
  • SUSPOINT V to SR3_M1 T1, T2, and T3. Which are the OSEMs related to the V, R, and P degrees of freedom of SR3.
  • SUSPOINT L to SR3_M1 LF, and RT. Related to the L and Y degrees of freedom.
  • SUSPOINT T to SR3_M1 SD. Related to the T degree of freedom
• These transfer functions are shown in the second attachment. Two interesting things to note:
  • None of them asymptote to -1. In amplitude, they hover around 0.75 or so.
  • The Vertical sensors are backwards. This is not important for what we're doing, we will calibrate by using the absolute value.
• We can get the scaling factors needed to make them asymptote to one by fitting the individual OSEM transfer functions to the model.  We fit by using linear regression between 5 and 15 Hz. The scaling factors calculated from the figures in the second attachment are:
  • T1 needs to be multiplied by:   2.4539
  • T2 needs to be multiplied by:   1.4819
  • T3 needs to be multiplied by:   1.4125
  • LF needs to be multiplied by:   1.3206
  • RT needs to be multiplied by:   1.3705
  • SD needs to be multiplied by:   1.3806
• Therefore, after we multiply the OSEMINF gains that were in place at the time of measurement by these scaling factors, the new OSEMINF gains should be:   
  • T1: 3.627
  • T2: 1.396
  • T3: 1.345
  • LF: 1.719
  • RT: 1.490
  • SD:1.781
• The T1 gain is egregiously high, which makes all of us a bit nervous. Oli has been in the process of checking if these numbers actually make sense. These results will be posted in another log... This one is already too long.