I tuned the Y2L gains in the same way as in 77539.
I've added two templates to userapps/asc/h1/templates/manually_tune_P2L.xml and manually_tune_A2L.xml
These templates have excitations for LOCK P (or Y) for each suspension at 30 Hz. In all the quads, we have bandstops for 30 Hz in ISCINF_P and Y (FM7). To do this I turned all 8 of those filters on, then one at a time inject 30 Hz into Lock for each DOF, checking for the height of the peak in DARM, coherence with the injection, and the transfer function of the excitation to DARM. I changed the gain to improve the transfer function until the phase flips.
If this has to be done frequently we should make a script that will do this, as it seems that the script that calculates based on the ratio of transfer functions doesn't work well.
The attachment shows that the improvement in DARM from today's commissoning time mostly comes from SRCL feedforward (and maybe the ESD bias tuning), but that the CHARD Y coherence hasn't changed much.
This may already be known, but in case it is not I am posting it in the aLOG again. In Fscan spectra, we can see the 960 Hz and 961 Hz DuoTone signal in h(t). I don't recall seeing this in previous observing run data. Is the DuoTone signal expected to be seen in h(t)? It is hard to see on the summary pages, but it can be seen in the Fscan plots or interactive spectrum. I attach a zoom from the interactive plots from May 1, but this can also be seen as far back as the start of O4a. It is also seen at L1.
Just wanted to add in a DARK spectrum as reference to this, indicating this is coming from the local electronics chain, and given I see some of this on the same ADC but non-DCPD channels, likely within the chassis itself. I also see even more of a 1 Hz forest than Evan's plot. See for example LLO alog: 71027.
Lockloss during comissioning time at 17:52UTC, 1 issue relocking which was due to the alignment not being the best.
We just returned to Observing at 19:31 UTC, I accepted SDF diffs for Sheilas SCRFF gain and Y2L measurements.
18:21 UTC, SRM saturation then LL. The ASC loops were not done working when GRD advanced us to turn on BS_STAGE2
I think what happened here was that the ASC had not converged before the guardian moved on, and probably the BS ST2 glitch caused the lockloss. (I haven't looked into this).
It would be great for someone to look carefully at the timing of this lockloss, compared to the BS glitch. It would also be good to compare this to a lock when we survive the BS glitch, (the next one), to see if there is a difference in the alignment signals or build ups that we could use as a check for the automation.
HEPI HAM1 watchdog trip, ACT. Potentially from a jack being used in the optics lab
https://ldas-jobs.ligo-wa.caltech.edu/~lockloss/index.cgi?event=1398707582
I adjsuted the gain of the SRCLFF filter while running a SRCL injection to reduce the coupling to DARM. (Screenshot attached). I've add the gain of 1.15 to the lscparams file so that the guardian will use this gain in future locks.
This is similar to what Gabriele did in 77492, and the calibration of traces in his screenshot is the same as mine (they are made using the same template.) Gabriele's "new FF" (red trace, -160 dB at 30 Hz) is giving worse performance today, shown by the blue trace "Old FF" in my plot, (-145dB at 30 Hz).
So it seems the SRCL FF gain that we need has changed quite a bit. This may be because of the OMC alignment offsets that Jennie Wright added to improve our optical gain in 77543
Thu May 02 10:15:33 2024 INFO: Fill completed in 15min 29secs
Gerardo confirmed a good fill curbside.
We've started comissioning which will run from 16:00 - 19:00 UTC (9am - 12pm PST). Some of the plans include, SQZ tuning, PEM injections, SRCL FF, and Y2L.
TITLE: 05/02 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing at 153Mpc
OUTGOING OPERATOR: Corey
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 5mph Gusts, 4mph 5min avg
Primary useism: 0.01 μm/s
Secondary useism: 0.09 μm/s
QUICK SUMMARY:
TITLE: 05/02 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 151Mpc
INCOMING OPERATOR: Corey
SHIFT SUMMARY: During relocking we were able to catch DRMI without needing to go through PRMI, but had locklosses from ENGAGE_DRMI_ASC and TURN_ON_BS_STAGE2 before I started an initial alignment. During initial alignment we couldn't get past WFS_CENTERING_SRY, so I just took us out of IA and started relocking. LVEA is still in LASER HAZARD.
LOG:
22:49 Detector Locked for 2 hours
00:10 Dropped Observing to run SQZ and regular calibrations
00:19 Went to NLN_CAL_MEAS for calibration measurements
00:30 Earthquake mode activated
00:50 Back to NOMINAL_LOW_NOISE and Observing
01:00 Seismic to CALM
04:59 Lockloss
05:10 Lockloss from ENGAGE_DRMI_ASC
05:18 Lockloss from TURN_ON_BS_STAGE2 - started an initial alignment
05:37 - 05:45 Stuck at SRC alignment
- Constant SRM, IFO_OUT, SQUEEZE_OUT saturations
- We weren't able to get past WFS_CENTERING_SRY, so I took us to DOWN
- Backed out of initial alignment and started relocking
06:27 NOMINAL_LOW_NOISE
06:30 Observing
Start Time | System | Name | Location | Lazer_Haz | Task | Time End |
---|---|---|---|---|---|---|
21:25 | SQZ | Terry, Camilla | Opt Lab | Local | SHG work, new CO2 test | 23:51 |
22:09 | PCAL | Rick, Fransisco | PCAL lab | local | PCAL tasks | 00:09 |
23:16 | VAC | Janos, Jordan | MY | n | Turn off CP3 pump | 23:31 |
06:30 UTC Observing
Currently Observing and have now been locked for 6 hours. Wind is calming down
Ran bb calibration measurements and simulines between 05/02/2024 00:10 and 00:50 UTC. *Earthquake mode was activated at 00:30UTC and stayed activated through the rest of the measurements, but I presume should have no effect?
Broadband
Started: 2024/05/02 00:20:20UTC
Output file: /ligo/groups/cal/H1/measurements/PCALY2DARM_BB/PCALY2DARM_BB_20240502T002020Z.xml
Simulines
Started: 2024/05/02 00:27:28UTC
Output files:
/ligo/groups/cal/H1/measurements/DARMOLG_SS/DARMOLG_SS_20240502T002728Z.hdf5
/ligo/groups/cal/H1/measurements/PCALY2DARM_SS/PCALY2DARM_SS_20240502T002728Z.hdf5
/ligo/groups/cal/H1/measurements/SUSETMX_L1_SS/SUSETMX_L1_SS_20240502T002728Z.hdf5
/ligo/groups/cal/H1/measurements/SUSETMX_L2_SS/SUSETMX_L2_SS_20240502T002728Z.hdf5
/ligo/groups/cal/H1/measurements/SUSETMX_L3_SS/SUSETMX_L3_SS_20240502T002728Z.hdf5
Robert, Anamaria
Yesterday we opened the viewports of the oplevs for both ITMX and ITMY to find the alignment of the CP's.
The procedure relies on the fact that the optics are not coated for red so we can see all four surfaces. The separation between the beams at this distance (~34m) is about 10cm due to the wedges (in the table below from the galaxy page). The test mass has a vertical wedge, thick down, so the AR beam will show up directly below. The CP is supposed to be perfectly parallel to the back surface so the closest surface of the CP (CP1) would land essentially right on top of the ITM AR beam. Then the CP has a similar size wedge, but horizontal, so the second CP surface would hit at the same level as CP1 and ITM AR but to the left or right, depending which ITM.
The first plot attached shows the nominal view of these beams as seen at the oplev viewport on the white page. The yellow pages were attached to the lexand covering the viewport and the beams were marked. The full view of all the beams no longer fits through the viewport due to the addition of nozzle baffles so we had to walk the oplev sender to find all the beams. For the ITMX we lucked out and the ITM AR beam was visible at the top gap of the baffle at the same time as the second AR reflection and the CP beam were visible in the aperture. As such we are able to scale the misalignments to the wedge value. We verified the CP beams by moving the CPs, and we scanned to find the second CP surface (CP2) horizontally at about the right distance from CP1.
wedge ITM/CP | misalignment | |
CP-X | 0.07/0.07 deg | 1.7 mrad down |
CP-Y | 0.08/0.07 deg | 0.55 mrad down |
By down I mean they are further pitched down towards the arm.
One would think that we have +/- 440 urad range in pitch on the R0, but it seems its range is much less than advertised. Even stranger, this was also found to be the case at L1, on both ITM R0. When we moved CPY, with respect to this calibration it only moves ~230 urad. So we cannot make it back to the nominal position of overlapping the ITM AR beam. For yaw we did a smaller step so more error on it, but it's about 60% of slider value. More on this later.
(CPY is the one that Robert found to modulate the noise from the MC tube baffle.) Speaking of the L1 experience, we even had to vent back in 2016 to fix one of these CP misalignments, which was too close to HR actually. The interesting thing to me, looking back, is that L1 still has a similar misalignment for CPX to the H1 CPY and we don't see as high noise coupling at the IMC tube.
CPX is very misaligned by comparison, but not linked to the MC tube scatter. Alena has agreed to help us track where these ghost beams land at P/SR3 and the scraper baffles, now that we know their exact orientation.
+Peter, Jeff
Regarding the reduced range of CPY R0, we checked what the BOSEMs and the coil current monitors had to say about the range during our optical measurement. Jeff kindly calibrated the RMSMONs so we could see what the current really is. The data is in the attached screenshot. We did not check the CPX but, as I mention above, we found this to be the case at LLO as well. For pitch I show F1, which gets the largest drive, for yaw I show one of F2/F3 which get identical drives. In terms of range, I define it as how far from 0 we can go, so half range technically, but it's max DAC output and current. If we want more range we have to decide if we can afford more than ~45mA on the BOSEMs.
CPY | Slider [urad] | range [%] | OSEM readback [urad] | Oplev meas [urad] | Coil current [mA] |
PIT | 440 | 100 | 1130 | 230 | 45 |
YAW | 200 | 33 | 160 | 120 | 16 |
I ran the SCAN_ALIGNMENT with new OMC alignment in 77543 after 3 hours into lock.
Then I ran the SCAN_SQZANG. Compared with the reference in NUC33, the squeezing in the bucket is similar, but the high frequency squeezing is a bit worse with new OMC alignment.
May 02 00:10UTC We just went into Commissioning to run our normal calibration sweep and calibrate sqz
00:50 Back to NOMINAL_LOW_NOISE and Observing