For FAMIS #26294: All looks well for the last week for all site HVAC fans (see attached trends).
(Camilla,Corey,Naoki, Vicky)
Once H1 got through a few hiccups at the DRMI ASC & BSC St2 steps, it went straight to NLN.
There were some Squeezer items which needed to be changed:
I made an attempt at updating Camilla's PSAMs double raster script to include alignment scans to optimize the squeezing throughput at each step and to automate measurements of FDS and FDAS spectra:
/opt/rtcds/userapps/release/sqz/h1/scripts/PSAMs_double_raster_v2.py
This should roughly replecate the functionality of the PSAM scan automation code used at Livingston (llo 64645). It likely still requires debugging, but I wanted to tag it here before I leave.
Naoki, Camilla, Eric
We've decided to try out our other candidate PSAM values for a few days. While retuning, we also took some FDS/AS and FIS/AS traces so we can characterize this operating point using Dhruva's interactive_sqz code.
PSAMs at 8.8/-0.7
Measured NLG = 17.07 (following 76542). Adjusted OPO temperature to 31.475
PSAMs moved to 7.5/0.5, walked alignment back manually on ZM4/5 using trend from Tuesday, Ran Scan_alignment for FDAS.
Data:
There was a fair amount of A2L work going on concurrently which may have been altering the technical noise quite a bit across the dataset. We intended to grab another NoSQZ at the end, but there was lock loss :(
We are going to leave things at this PSAM setting tonight with H1:SQZ-CLF_REFL_RF6_PHASE_PHASEDEG = 190.
In the beginning of next lock, we ran the SCAN_SQZANG and the sqz angle was set at 199. However, the range seems better with 192. So we set the sqz angle at 192.
Jennie W, Sheila, Jenne
We did steps of 1 up in PITCH for camera offset servo 2 which controls the beam spot on ETMX by moving ITMX and ETMX, as suggested by this overnight test Camilla and I did.
This improved the build-ups and we went past the optimum point which we found to be CAM_PIT2_OFFSET = -173, so we set the offset to this. The optimum point is shown by the right most cursor in this image.
We did steps of 1 up in YAW for camera offset servo 3 which controls the beam spot on ETMY by moving ITMY and ETMY, as suggested by this overnight test Camilla and I did.
This improved the build-ups and we went past the optimum point which we found to be CAM_YAW3_OFFSET = -349.5, so we set the offset to this. The optimum point is shown by the right most cursor in this image. There was confusion as the PITCH and YAW degrees are cross-coupled (this confused us as one must wait for the pitch servo to converge while changing the yaw degree of freedom).
We then tried to optimise our last DOF for the camera servos: PITCH for servo 3. We first moved the offset up and then down, but made the build-ups worse each time. By this point we had increased thje gain of the camera servo filter banks by 2 to speed up the converging. CAM_PIT3_OFFSET should be set to its nominal at -230 counts.
Then we ran the A2L gain scripts we used the other day successfully to optimise thse loops to match the new arm alignment. During running of this script we lost lock, not sure why.
We did not add these new offsets to the guardian because of the lock loss, we will do them together with the A2L optimisation during the nest commissioning period.
The A2L script is is userapps/isc/h1/scripts and is called run_all_a2l.sh
Looking at the lockloss while running the A2L script:
It completed the excitations and gain adjustment for ITMX and ITMY yaw, but lost lock during the Y2L exctitation for ETMX. Next time we get a chance to try this, we could try running ETMX Yaw with a much smaller excitation and ask the code not to set the gain automatically.
The ndscope template used to make this screenshot is in sheila.dwyer/ndscope/ASC/A2L_script.yml
TITLE: 04/12 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Lock Acquisition
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 8mph Gusts, 5mph 5min avg
Primary useism: 0.02 μm/s
Secondary useism: 0.16 μm/s
QUICK SUMMARY:
Getting hand-off from TJ as H1 was recovering from a lockloss (from a 17.5hr lock). So far we have had 3-locklosses in a row toward the end of DRMI turning on ASC (to most recently when turning on BS's Stage-2----contemplating an Initial Alignment if there is a 4th lockloss!
TITLE: 04/12 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Lock Acquisition
INCOMING OPERATOR: Corey
SHIFT SUMMARY: Currently recovering from a 17.4 hour lock. Commissioning time from 1pmPT today and has just wrapped up. Handing off to Corey to finish locking.
LOG:
Fri Apr 12 10:12:09 2024 INFO: Fill completed in 12min 5secs
Gerardo confirmed a good fill curbside.
TITLE: 04/12 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing at 158Mpc
OUTGOING OPERATOR: Ryan C
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 5mph Gusts, 1mph 5min avg
Primary useism: 0.01 μm/s
Secondary useism: 0.13 μm/s
QUICK SUMMARY: Locked for 10 hours. We've had a handful of EX saturations throughout the night, but our range is looking good. Commissioning planned for today at 1pm PT.
Below is the summary of the DQ shift for the week from 2024-04-01 to 2024-04-07
The full DQ shift report with day-by-day details is available at https://wiki.ligo.org/DetChar/DataQuality/DQShiftLHO20240401
Since PMC is so sensitive to acoustic noise I was curious if PMC added additional contributions to the sqz phase noise. So, I did the same SQZ phase noise budget analysis that was done in O3. The explanation and the methodology can be found in P2200287 chapter 6.3.1 onward.
PMC noise contribution to sqz phase noise is 0.59 mrad. There's no need to put extra efforts into damping the cavity unless people are annoyed that it loses lock everytime we use some of the motorized half wave plate.
The FWHM and FSR of the PMC was measured by Vicky at MIT. They are 175MHz and 713 MHz respectively. We didn't repeat this measurement after the installation because the LVEA was too loud and the finesse is high for s-pol (4070).
The Vpp calibration for the PMC is 2.22 Vpp/FWHM. This was measured after the PMC was installed. In order to fit the transfer function I had to multiply a factor of 1.5. Vicky mentioned the PMC PZT is very nonlinear so my V/Hz calibration could be off. If that's true then the PMC trace needs to be multiplied by a factor of 1.5.
I had to multiply a factor of 0.33 to the CLF and LO loop in order to fit the transfer function. Even after using the new VCO V to Hz calibration that Daniel measrued. I suspect the Vpp/rad calibration was over estimated due to RLF. If that's true then the LO and CLF traces shown in this alog needs to be multiplied by a factor of 0.33.
The PZT driver for the PMC is the same as in the SHG and the OPO
This plot shows overall noise contributions to the sqz angle from all the sqz loops. The data were taken in between 11-18 March 2024 (pre O4b). The rms from different loops are added in quadrature to get sqz phase noise. I don't have filter cavity red lengthnoise data handy but a rough calculation from Dhruva's measurement back in February last year the lengthnoise should be sitting at 0.3 mrad/sqrt(Hz) at a 100Hz. If the rms scales the same way that's 3 mrad added in quadrature with the rest of the noise contributions.
This screenshot shows more details analysis from PMC, SHG, OPO, CLF (6dBm and -23dBm) along with the transfer functions and sensing noise.
A separate screenshot for LO loop, low and high CLF power, with the transfer functions and sensing noise.
The table below lists all the noise contribution from sqz loops to sqz angle. Until we achieve a single digit % loss these numbers are negligible. The major contribution to sqz angle pahse nosie still comes from the IFO control signal sidebands. I didn't remeasure the TTFSS noise so I used the in-loop rms number from last year.
SQZ phase noise | Low CLF (mrad) | high CLF (mrad) |
TTFSS (phi laser) | 0.03 | 0.03 |
PMC | 0.59 | 0.59 |
SHG | 0.089 | 0.089 |
OPO | 0.11 | 0.11 |
CLF | 2.25 | 0.37 |
LO | 2.5 | 0.91 |
FC | 2.6 | 2.6 |
total | 4.294359207 | 2.844999297 |
TITLE: 04/12 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 156Mpc
INCOMING OPERATOR: Ryan C
SHIFT SUMMARY: Mostly quiet shift with just one lockloss. Reacquisition was fairly straightforward; I only had to manually find DIFF IR.
H1 has now been locked for 2 hours.
LOG:
No log for this shift.
We see occasional excess nosie around 32.5 Hz in the h(t). This feature has been there for a long time, was present even in O3. They were identified before and were a-logged, for example 52796 (?), 73601. The first plot in this a-log shows the feature in last week's data. A corresponding featuer is seen in almost all the accelerometers and ground seismometers in the corner station (the second and third plots show the HAM6 and PSL accelerometers data while the fourth plot shows the HAM2 STS). In addition to the 32.5 Hz feature, if we squint, we can also a 38-39 Hz feature in h(t) which seems to presnt only in the vibration sensors in the PSL/HAM1/HAM2 region, so maybe there is a coupling is in that region. Not all features we see in those sensors show up in h(t), not atleast very strong, so maybe something special about these frequencies.
Lockloss @ 03:37 - no obvious cause, but there was an ITMX saturation immediately before the lockloss. First signal that shows motion is LSC-DARM.
Online lockloss tool is down.
H1 back to observing at 04:58 UTC. Waited in OMC_WHITENING for 10 minutes to damp rung up violin modes on ETMX.
State of H1: Observing at 163Mpc
H1 has now been locked for 9.5 hours. Very quiet evening so far.
HAM1 ASC FF was off from 1396381762 to 1396382969 (20 minutes starting 90 minutes into lock). Using this data I could retune the feed forward filters that subtract HAM1 motion from the ASC signals.
I based the attached jupyter code on an older version, and automated the subtraction training for all pitch and yaw ASC signals (CHARD, INP1, PRC2, DC1 and DC2).
Looking at the filters that are loaded now, we used to do the FF only for the pitch degrees of freedom. The subtraction seems to be doing something good in yaw too, so I suggest we upload and try the yaw feedforward filter.
The first plot shows the expected subtraction predicted by NonSENS. The second plot shows the absolute value of the transfer functions.
Finally, the attached text file contains the foton filter definitions for all the feedforward filter banks. I haven't upload those flter to foton, and not tried them yet. Before each filter there is the name of the filter bank where it should be loaded, for example H1:HPI-HAM1_TTL4C_FF_CART2ASCP_1_1
[Jennie, Jim, Gabriele]
We tried the new filter, and there's something wrong with them. Even with a gain of 0.5 (instead of 1) they make some of the ASC signals much worse, see attached plot.
We'll use the time we got today with FF off (starting 1396987833 and lastring 10 minutes) to debug the problem and retune the FF
In the attached plot: green = FF off, blue = nominal FF, red = new FF with half gain
Gabriele, Jim, Jennie W
I saved the new HAM FF filters in H1SEIPROC foton file. These will only be loaded in during our commissioning window tomorrow.
The code attached to this alog had a bug that produces the wrong filters. Attached an updated version, hopefully without any more bugs. Also attached the new text filw with all the filters.
The two plots show the expected subtarction and the absolute value of the filters.
Gabriele's new coefficients have been loaded into SEIPROC and are available, but haven't been turned on or tested yet.