Sheila, Naoki, Vicky, Camilla

As we continue to see the nominal SQZ angle change lock-to-lock (attached BLRMs). We edited SQZ_MANAGER to scan sqz angle (takes 120s) every time the SQZ locks, i.e. every time we go into NLN.

In  SQZ_MANAGER we have:

• Added a state FC_WAIT_FDS after SQZ ASC, which asks the FC to lock and waits up to 5 minutes (this used to be done in nominal state FDS). 
• Changed the next nominal state to SCAN_SQZANG (120s scan to get best squeezing at 350Hz BLRMs, may still need improvements).
  • This can be bypassed if we don't like this addition be removing the weighting from '('FC_WAIT_FDS', 'FREQ_DEP_SQZ', 3)'
• I added an LO_checker_FDS() to FC_WAIT_FDS  and FDS to come back to FDS_READY_IFO if the LO unlocks to avoid copy-pasting code everywhere.
• SCAN_SQZANG still has paths to/from FDS so we can still request it whenever.
• Old and new graphs attached. svn commit 27520.

We tested this taking SQZ_MANAGER down and back up, it went though SCAN_SQZANG as expected and improved the SQZ by 1dB, range improved by ~10MPc.

We'll want to monitor that the change as SCAN_SQZANG may not give us the best angle at the start of the lock when SQZ is very variable. We expect this won't delay us going into observing as only added 120s and ISC_LOCK is often still waiting for ADS to converge during  this time.

Ran a broadband and simulines calibration sweep at 15:30 UTC and successfully finished at 16:01 UTC.

Now going into planned Wednesday comissioning.

Start:

PDT: 2024-04-17 08:39:27.631946 PDT

UTC: 2024-04-17 15:39:27.631946 UTC

GPS: 1397403585.631946

End:

PDT: 2024-04-17 09:00:59.127599 PDT

UTC: 2024-04-17 16:00:59.127599 UTC

GPS: 1397404877.127599

2024-04-17 16:00:59,060 | INFO | File written out to: /ligo/groups/cal/H1/measurements/DARMOLG_SS/DARMOLG_SS_20240417T153928Z.hdf5

2024-04-17 16:00:59,066 | INFO | File written out to: /ligo/groups/cal/H1/measurements/PCALY2DARM_SS/PCALY2DARM_SS_20240417T153928Z.hdf5

2024-04-17 16:00:59,071 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L1_SS/SUSETMX_L1_SS_20240417T153928Z.hdf5

2024-04-17 16:00:59,075 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L2_SS/SUSETMX_L2_SS_20240417T153928Z.hdf5

2024-04-17 16:00:59,079 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L3_SS/SUSETMX_L3_SS_20240417T153928Z.hdf5

ICE default IO error handler doing an exit(), pid = 685800, errno = 32

TITLE: 04/17 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing at 146Mpc
OUTGOING OPERATOR: Tony
CURRENT ENVIRONMENT:
    SEI_ENV state: EARTHQUAKE
    Wind: 11mph Gusts, 7mph 5min avg
    Primary useism: 0.30 μm/s
    Secondary useism: 0.12 μm/s
QUICK SUMMARY:

IFO is in NLN and OBSERVING

TITLE: 04/17 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Aligning
INCOMING OPERATOR: Ryan S
SHIFT SUMMARY: The wind was really bad during my shift and caused the time between the 23:39 LL and NOMINAL_LOW_NOISE to be 3.75 hours. We had a second lockloss at 06:44UTC and just finished an initial alignment.
LOG:

23:00 Detector in NOMINAL_LOW_NOISE and troubleshooting going on wrt sqz

23:34 Into Observing

23:39 Lockloss

- Relocking -
23:57 Lockloss from AQUIRE_PRMI
23:59 Lockloss from LOCKING_ALS
00:00 Started Inital Alignment

00:20 DIAG_MAIN message that ALSY polarization is above 20%
    - I using Camilla's instructions(58773) to find the right screen, and went to follow the instructions there, but all I did was press ON and then press Restore like it said, but just by clicking those the ALSY polarization value went down to 7% and ALSX up to 12%, so without needing to adjust anything I pressed OFF.

00:22 Initial Alignment completed
00:40 Lockloss from ACQUIRE_DRMI_1F
00:43 Lockloss from FIND_IR
00:48 Lockloss from LOCKING_ALS
00:51 Lockloss from FIND_IR
    - Sitting in DOWN for a bit
01:00 Trying relocking again
01:07 Lockloss from ACQUIRE_DRMI_1F
01:10 Lockloss from LOCKING_ALS
    - Sitting in DOWN for a bit again
02:00 Trying to relock again again
    - Wind still > 30mph
02:14 Started another Initial Alignment
    - Went through CHECK_MICH_FRINGES and then ifo wanted to do CHECK_MICH_FRINGES again
02:40 Initial Alignment done
- Done relocking -

03:23 NOMINAL_LOW_NOISE
03:26 Observing

06:22 Lockloss

- Relocking -
06:44 I took us to initial alignment because we couldn't get past ACQUIRE_PRMI
07:00 Initial alignment done

Lockloss 04/17 06:22 for unknown reasons

After three hours of not being able to get past ACQUIRE_DRMI due to the high wind, we finally are making it up and are currently at MAX_POWER.

Closes FAMIS#26292, last checked 77145

Corner Station Fans (attachment1)
All fans are looking normal and within range.

Outbuilding Fans (attachment2)
MX_FAN1_370_1 is still jumping in noise like it's been doing for the last few weeks. These jumps in noise are still well within range. 
All other fans are looking normal and are within range.

Lockloss 04/16 23:39UTC - IX saturation at lockloss

The HASH_INT channel was updated at 16:00 and its new value was accepted into CDS SDF. These two channels were removed from h1calcs SDF by hand editing the snap file.

As a test that the cal_hash_ioc restores it values on startup, we restarted it at 16:30. CDS SDF didn't notice it had gone, the EDC connected channel counter dropped by 5 for about 15 seconds.

TITLE: 04/16 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Commissioning
OUTGOING OPERATOR: Ibrahim
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 25mph Gusts, 19mph 5min avg
    Primary useism: 0.15 μm/s
    Secondary useism: 0.14 μm/s
QUICK SUMMARY:

Locked for almost 2 hours, Jim is doing some last minute tests and sqz team is trying to last minute troubleshoot the sqzer before we go into observing without sqz

J. Oberling, T. Guidry, R. Crouch

Progress since our last update.

When we ended last, we had large Z axis deviations for our PSI monuments that we speculated was due to the fit being unable to pick up on the tilt of the X axis in our global coordinate system, since the height marks we were using for Z axis alignment were all in a line along the Y axis.  To test this, we decided to try aligning the FARO in the local LVEA coordinate system, then translating that alignment to our global coordinate system.  We first tried this on 4/9/2024, then again with a slightly different method today, 4/16/2124.

4/9/2024

We first tried assuming the LVEA is perfectly flat; in other words, we used the same Z axis coordinate for all PSI monuments.  With a new Z axis coordinate for BTVE-1 (-1060.3 mm) that we tied back to BSC2 Z=0, and our differential height measurement from alog 75669, we calculated a new Z axis coordinate for PSI-1 of -1885.4 mm.  We then used this Z axis coordinate for PSI-2 and PSI-6 to give us a very rough Z axis alignment.  We then followed the same method we used in alog 76889 to align the FARO, except we did not convert the Z axis coordinates to our global coordinate system, we left them in LVEA local.  In the end, we were using BTVE-1, PSI-1, PSI-2, and PSI-6 for X and Y axis alignment, and BTVE-1, 901, 902, and 903 for Z axis alignment.  At first we thought this looked pretty good, but then we noticed that we had some significant deviations in X axis coordinates for 901, 902, and 903 that were not there before we finalized the alignment.  Turns out that excluding PSI-2 from the Z axis alignment drags everything off in X by several mm, and the alignment is still incapable of accurately resolving a Z coordinate for PSI-2 (16.3 mm deviation!).  It's almost like the PolyWorks alignment algorithm thinks PSI-2 is rotated/tilted somehow w.r.t. the other monuments, we really don't have an explanation for it.  This can be seen in the 1st 2 attached pictures.  Regardless, it seems like this isn't the route to go down, so we ended the day at this point.  Also, the maintenance window was almost over so we had to shut things down anyway.

Before completely shutting down, we did try converting from the local coordinate system to the global one.  PolyWorks allows the user to set a new coordinate system by several methods, most importantly to us by translation and rotation about known axes.  In other words, we can set a new Cartesian coordinate system, and translate and rotate it however we need.  This is good for our purposes, as we can enter the rotation of our X and Y axes that converts from LVEA local to site global.  Recall that, if you are sitting at the origin of the IFO's coordinate system, the global X axis is tilted down by 619.5 µrad w.r.t. the local LVEA X axis and the global Y axis is tilted up by 12.5 µrad w.r.t. the local LVEA Y axis.  PolyWorks uses axis tilt as a roll of the axis, so we enter the Y axis tilt as an X axis roll and the X axis tilt as a Y axis roll (we don't translate the axes at all, the origins are supposed to be the same spot).  This all seemed to go smoothly, but left a few things that we didn't have time to dig into: It looked like the rotation of the X and Y axes also induced a rotation of the Z axis, even though that is supposed to be held constant, and it looked like it was rotating too much (our Z axis coordinates changed more than we expected).  More to look into for next time.

Speaking of next time...

4/16/2024

Today we essentially did a repeat of last week, except we did not assume the LVEA was perfectly level.  Since we had the previous differential height measurements and the new BTVE-1 local Z axis coordinate, we used the differential height measurement data to calculate new LVEA local Z axis coordinates for PSI-1, PSI-2, and PSI-6.  It should be noted that we weren't really in love with way we had to do the differential height measurement for PSI-6, due to line of sight issues, so we entered that as a placeholder only, it was not included in any alignments.  To keep things consistent we used sphere features for BTVE-1, PSI-1, PSI-2, and PSI-6; this means we also included the correction for the sphere-fit rod, which measures the bottom of the monument punch and not the monument surface that the coordinate is registered to.  The new LVEA local Z axis coordiantes we used today, properly corrected for punch depth, are:

• BTVE-1: -1061.1 mm
• PSI-1: -1886.5 mm
• PSI-2: -1887.3 mm
• PSI-6: -1881.9 mm (placeholder only!)

Since these Z axis coordinates for PSI-1 and PSI-2 are ones we directly measured with the FARO, via differential height measurement w.r.t. BTVE-1, and have tied back to BSC2 Z=0, via our water tube level survey and differential height measurements, we also included them in the alignment routine; as stated previously PSI-6 was excluded from the alignment routine as we do not trust that number.  Following the same method previously used, we measured the X and Y coordinates for height marks 901, 902, and 903, and used our previously-measured Z axis coordinates from our water level survey.  The results of the final alignment routine are shown in the 3rd attachment; this is in the LVEA local coordinate system.  This is the closest we've yet been to something that looks like a good alignment to one of our coordinate systems (LVEA local in this case).  One thing we immediately notice, the measured X axis coordinate for BTVE-1 is reported as off by -1.2 mm.  At this point in time we really have no way to know if this is a true error in the placement of BTVE-1 or an error in our alignment routine.  It could be a result of the sphere fit rod, as we don't really trust its repeatability; probing method and who operates the rod has a large impact in the measurement, but we have no other way to probe BTVE-1 due to its dome shape.

We also took another shot at converting from the LVEA local coordinate system to our site global coordinate system.  We did this in the same was previously, setting up a new coordinate system and rotating the X and Y axes by our known rotations.  We immediately saw that, again, it appeared to be over-rotating.  I didn't get a picture, but using height mark 901 as an example.  It has an LVEA local Z axis coordinate of -55.2 mm, which, when using the listed X and Y coordinates for this mark, translates to a site global Z axis coordinate of -55.7 mm.¹  The new coordinate system kept putting the gloabl Z axis coordinate for 901 at -56.0 mm, 0.3mm below where it should be.  We were a little puzzled by this, and were initially thinking that PolyWorks was rounding up to the displayed number of digits after the decimal point, and not using the axis tilts as we entered them (for example, Y axis tilt in degrees is 0.000716, which the PolyWorks display rounds up to 0.001).  We set the display to 7 digits after the decimal and our entered angles were display properly, so this was not the cause.  Turns out it was a sign issue.  We had been told by PolyWorks support, back in 2022, that we needed to enter the opposite sign of our actual axis tilt due to the way PolyWorks references tilts w.r.t. the FARO.  We checked the Properties of the new coordinate system and noticed the IJK unit vectors for the Z axis did not have the correct signs.  In fact, it had both X and Y rotations listed as negative, when they should be opposite.  Correcting the signs the displayed the correct global Z axis coordinates; shown in the final attachment.  We still have the issue of the new coordinate system also rotating about the Z axis when it shouldn't.  This is best seen by looking at the nominal X axis coordinate for BTVE-1.  In the 3rd attachment, in LVEA local, BTVE-1 X is properly listed as 0.0.  In the final attachment, in site global, the nominal X for BTVE-1 is now -0.657mm.  In looking at the direction cosines for the LHO Corner Station as listed in T980044, there is a small rotation from global Z to local Z, which we did not implement.  Will test and see if implementing this small rotation corrects this.

We like this alignment, it's the best we've seen to date.  So, next steps are to start moving the FARO through the LVEA and measuring known points while setting up a volume of alignment monuments, in hopes that we can get enough monuments so we can set the FARO anywhere in the LVEA and be able to align it.  This will continue on Tuesdays as our schedules allow, until we are done.

1) Keeping this here for posterity, as it was my thinking as we were on the floor, but this is incorrect.  In writing this alog I realized that I got my direction cosine signs flipped when we were setting up the coordinate system transform in the PolyWorks software this morning.  *facepalm*  The proper global Z for 901 based on the X and Y axis coordinates listed in the referenced picture is -54.7 mm, not -55.7 mm.  This also means that we then flipped the signs for both direction cosines when we "corrected" the incorrect signs we initially saw with the new coordinate system.  I'm going to take a look tomorrow and see about correcting this, pretty sure we can do that "offline" without a FARO connected.  Will post any update as a comment to this alog.

Shiela, Naoki, Rahul, Kar Meng, Terry

Same as yesterday (77188), we are again today having trouble locking the FC. Wind is again constant at 0-20mph. Can get green flashes but no locking, even with FC feedback turned off, VCO locking also fails. 

Rahul changed the M1 coil driver state on FC1 and FC2 from state 1 (usually only used in TFs) to state 2: IFO nominal for other triples. State 2 contains a low pass filter. 

Rahul took FC2 P and L transfer functions, look healthy and same as 66414.

Rahul took FC2 OSEMINF spectrums and checked ther health, as previously had issues with FC1 BOSEMS  (72563). Can see the 0.3 to 0.4Hz peak, Rahul's not worried about it but we could check old data for this peak.

WP11812

Jamie, Jonathan, Erik, Dave:

The two CAL HASH channels (H1:CAL-CALIB_REPORT_HASH_INT and H1:CAL-CALIB_REPORT_ID_INT) were moved from the h1calcs model, where they were being acquired as single-precision floats, to a new custom EPICS IOC called cal_hash_ioc, where they are acquired as signed 32bit integers.

The h1calcs.mdl model was modified to remove the EPICS-INPUT parts for these channels. The model was then restarted.

The IOC, which was being tested with H3 channels, was modifed and rstarted to serve the H1 channels as integers.

The EDC was modified to add H1EPICS_CALHASH.ini to its master list. This added 5 channels the the DAQ, the two hash channels and three IOC status channels.

The EDC was restarted, followed in short order by a DAQ restart.

Lately it's been very difficult to fit an efficient SRCL feedforward filter, as reported many times by Camilla et al. (76993). Here I'm trying to figure out why. Spoiler alert: I don't have an answer yet.

The main problem with the SRCL FF filter (see first plot), is that the transfer function to fit has a large phase rotation, that looks basically like a phase advance (the opposite of a delay) of about 2 ms. This is very large, and being an advance, it can't be realized in a precise and simple wasy digitally.

First observation: we can fit a pretty good SRCL FF if we allow for unstable poles, i.e. poles with positive real parts (see second plot) Of course this is not something that can be implemented in the real time system. The fit ends up having a unstable complex pole at about 420 Hz and about 5 Hz. I have no intepretation for the origin of those poles, and they might very well be only a way to reproduce a phase advance (think of the Padé approximation for phase delays).

So the question is: what is the origin of this large phase rotation? It's not seen at LLO, for example see 70548

Second observation: this phase advance appeared after we switched the LSC FF from ETMX (full chain) to ETMY PUM. The third plot compares the MICH and SRCL feedforward to be fit in two cases: an old measurement when the FF was going to ETMX, and a more recent measurement with the FF going to ETMY PUM only. For both MICH and SRCL the orange traces (FF to ETMY) show a phase advanced with respect to the blue traces (FF to ETMX). For some reasons I don't fully understand, this rotation is more problematic for SRCL than for MICH, although fitting MICH has also been more difficult and the MICH FF is relevant at lower frequencies than SRCL, so maybe the phase advanced isn't that problematic.

Looking at the measurement of the MICHFF to DARM and SRCLFF to DARM, one can see that there seems to be an additional phase delay in the FF path through ETMY PUM with respect to the FF path through ETMX full chain. Since this transfer function is at the denominator when computing the ratio SRCLtoDARM/SRCLFFtoDARM that gives use the LSC FF to fit, this seems to explain the additional phase advance we observe.

The ETMY PUM L2 lock filter bank contains a "QPrime" filter module that compensates partially the additional 1/f^2 due to the actuation from L2 instead of L3. This filter however doesn't seem able to explain this additonal phase delay.

I'm now suspicious that there might be something wrong or mistuned in the ETMY L2 drive, maybe a whitening filter missing or not functioning properly or not properly compensated?

It would be worth doing a quick test in the next commissioning time with full IFO locked: inject some white noise on ETMX L2 L and ETMY L2 L and comapre the two transfer functions to DARM. In theory they should be equal, except for a sign difference. If they're not, then there must be something wrong with ETMY, since we're using ETMX L2 to lock without issues.