anthony.sanchez@LIGO.ORG - posted 15:37, Tuesday 15 July 2025 (85780)
HVAC Vibrometer Monthly Trends
Images attached to this report
Monthly Dust trends FAMIS 37254
I've attached the Dust mon plots for the past month.
I have moved the DHARD control to be distributed between AS A and B RF45 Q instead of only on AS A RF45 Q to see if we can reduce the noise in DHARD.
On Monday, I ran an injection in DHARD P and Y (see pitch, see yaw) and determined that both AS A and B RF45 Q have equal SNR for DHARD. The difference is the phase, AS B RF45 is the opposite sign as AS A RF45. Therefore, I figured we could try a new sensing scheme, instead of using just AS A RF45 Q, we would use 0.5*A and -0.5*B signals.
Today, I first tested this by putting in my new input matrix into DC7 pitch and yaw. I watched my new signal compared to the nominal DHARD signal during the engagement of DHARD WFS. There were no offsets in the signal. I ran a quick passive transfer function to determine that the signals have the same magnitude and phase.
Then, Tony was holding us at 2 W to sweep the LVEA before observing, so I used the opportunity to try the new matrix. I put the new matrix in the DHARD B path, aka the DHARD blend filter path. I then ramped halfway between DHARD A, which is just on AS A, and DHARD B which is distributed between AS A and B. This worked well, so I ramped the rest of the way. This worked perfectly for both pitch and yaw. I decided I liked this, so I put the new intrix back in DHARD A and ramped back so I wouldn't have to deal with extra SDF diffs.
I continued to monitor the signals as we powered up and saw that everything was performing well. I updated the guardian to use this new intrix- this matrix is set in the DARM_TO_RF state, and then DHARD is first engaged at DHARD_WFS.
Sensibly, this corresponds to about a sqrt(2) reduction in the DHARD noise above 10 Hz, comparing the signals from today to signals during observing last night.
I accepted the differences in observe SDF as well. Note that I also accepted a CHARD tramp due to some other ASC changes I reported in this alog.
Leo, Jennie, Camilla, WP 12677
Setup steps:
Opened up the back side of SQZT7 and used the Nanoscan beam profile to profile the SQZ beam in 5 points between the LPM and MR13 (layout D2000242) with the nominal PSAMS settings [ZM4 92V Strain 6.0, ZM5 109V Strain -0.4]. And repeated with PSAMS set to 0V,0V [ZM4 0V Strain 2.25, ZM5 0V Strain -5.4], results attached, Leo will analyze.
To change PSAMS to Voltage we wanted:
Before we went back to squeezing, reverted the PSAMS offsets and put the servos back on (after clearing their histories), reduded SEED power back down to 0.6mW, also adjusted waveplates for PUMP rejected power, disabled picos and turned off OPO EXC that the dither lock left on.
TITLE: 07/15 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 132Mpc
OUTGOING OPERATOR: Tony
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 28mph Gusts, 16mph 3min avg
Primary useism: 0.07 μm/s
Secondary useism: 0.17 μm/s
QUICK SUMMARY:
Currently Observing at 137 Mpc and have been Locked for 27 minutes. The wind is reaching 30mph.
LVEA Has been Swept,
I found that there was a hissing coming from an open connection from a Kobelco compressor.
Jordan has since shut that off.
WP 12675
WP 12676
ECR E2400330
Drawing D0901284-v5
Modified List T2500232
The following SUS SAT Amps were upgraded per ECR E2400330. Modification improves the whitening stage to reduce ADC noise from 0.05 to 10 Hz. The EX PUM SAT Amp was NOT upgraded.
| Suspension | Old | New | OSEM |
| ETMX MO | S1100128 | S1100075 | F1F2F3SD |
| ETMX MO/RO | S1100079 | S1100163 | RTLF/RTLF |
| ETMX RO | S1100149 | S1100132 | F1F2F3SD |
| ETMX UIM | S1000297 | S1100140 | ULLLURLR |
| TMSX | S1100098 | S1100150 | F1F2F3LF |
| TMSX | S1000292 | S1100058 | RTSD |
| MC2 | S1100107 | S1100071 | T1T2T3LF |
| MC2/PR2 | S1100087 | S1100147 | RTSD/T1T2 |
| PR2 | S1100172 | S1100121 | T3LFRTSD |
F. Clara, J. Kissel
As of 2025/07/25 00:00 UTC, the TMSX satamp box for F1/F2/F3/LF has been swapped from S1100150 to S1100122
See 85980 for more info
Here's the characterization data and fit results for S1100075 , assigned to ETMX M0's F1F2F3SD OSEMs (Fil refers to this as ETMX MO F1F2F3SD). The data was taken per methods described in T080062-v3. The data was processed and fit using ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ plotresponse_S1100075_ETMX_M0_F1F2F3SD_20250710.m Explicitly, the fit to the whitening stage zero and pole, the transimpedance feedback resistor, and foton design string are Optic Stage Serial_Number Channel_Number OSEM_Name Zero_Pole_Hz R_TIA_kOhm Foton_Design ETMX M0 S1100075 CH1 F1 0.0971:5.31 120 zpk([5.31],[0.0971],1,"n") CH2 F2 0.0973:5.33 120 zpk([5.33],[0.0973],1,"n") CH3 F3 0.0979:5.36 120 zpk([5.36],[0.0979],1,"n") CH4 SD 0.0953:5.21 120 zpk([5.21],[0.0953],1,"n") The attached plot and machine readable .txt file version of the above table are also found in ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ As LHO:85626 discusses, I'm intentionally excluding the fit of transimpedance gain from the foton design string, and so I've stopped using the R_TIA_kOhm as a knob in my by-hand fitting of the zeros and poles. Hence, you'll find that from here on, R_TIA_kOhm will almost always be the default 120 kOhm value I've found that works with the measured data and changing only the zero:pole frequency.
Here's the characterization data and fit results for S1100163 , assigned to ETMX M0/R0's LFRT/LFRT OSEMs (Fil refers to this as ETMX MO/RO RTLF/RTLF above). The data was taken per methods described in T080062-v3. The data was processed and fit using ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ plotresponse_S1100163_ETMX_M0R0_LFRTLFRT_20250710.m Explicitly, the fit to the whitening stage zero and pole, the transimpedance feedback resistor, and foton design string are Optic Stage Serial_Number Channel_Number OSEM_Name Zero_Pole_Hz R_TIA_kOhm Foton_Design ETMX M0R0 S1100163 CH1 LF 0.0948:5.18 120 zpk([5.18],[0.0948],1,"n") CH2 RT 0.0954:5.21 120 zpk([5.21],[0.0954],1,"n") CH3 LF 0.0969:5.30 120 zpk([5.30],[0.0969],1,"n") CH4 RT 0.0947:5.17 120 zpk([5.17],[0.0947],1,"n") The attached plot and machine readable .txt file version of the above table are also found in ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ As LHO:85626 and the above LHO:86028 discusses, R_TIA_kOhm is the default 120 kOhm.
Here's the characterization data and fit results for S1100132 , assigned to ETMX R0's F1F2F3SD OSEMs (Fil refers to this as ETMX RO F1F2F3SD above). The data was taken per methods described in T080062-v3. The data was processed and fit using ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ plotresponse_S1100132_ETMX_R0_F1F2F3SD_20250710.m Explicitly, the fit to the whitening stage zero and pole, the transimpedance feedback resistor, and foton design string are Optic Stage Serial_Number Channel_Number OSEM_Name Zero_Pole_Hz R_TIA_kOhm Foton_Design ETMX R0 S1100132 CH1 F1 0.0943:5.17 120.75 zpk([5.17],[0.0943],1,"n") CH2 F2 0.0960:5.25 121.00 zpk([5.25],[0.0960],1,"n") CH3 F3 0.0963:5.28 121.25 zpk([5.28],[0.0963],1,"n") CH4 SD 0.0970:5.33 120.75 zpk([5.33],[0.0970],1,"n") The attached plot and machine readable .txt file version of the above table are also found in ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ This sat amp actually needed some fit transimpedance gain, so I report it here. But, again, it's not used in the compensation filter.
Here's the characterization data and fit results for S1100140 , assigned to ETMX L1's ULLLURLR OSEMs (Fil refers to this as ETMX UIM ULLLURLR above). The data was taken per methods described in T080062-v3. The data was processed and fit using ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ plotresponse_S1100140_ETMX_L1_ULLLURLR_20250715.m Explicitly, the fit to the whitening stage zero and pole, the transimpedance feedback resistor, and foton design string are Optic Stage Serial_Number Channel_Number OSEM_Name Zero_Pole_Hz R_TIA_kOhm Foton_Design ETMX L1 S1100140 CH1 UL 0.0943:5.14 120.5 zpk([5.14],[0.0943],1,"n") CH2 LL 0.0965:5.26 120.5 zpk([5.26],[0.0965],1,"n") CH3 UR 0.0943:5.14 120.5 zpk([5.14],[0.0943],1,"n") CH4 LR 0.0961:5.24 120.5 zpk([5.24],[0.0961],1,"n") The attached plot and machine readable .txt file version of the above table are also found in ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ Similar to S1100132, I found I needed to slightly adjust the transimpedance to get a good phase fit of the zero frequency while getting magnitude scale to the ~1.000 +/- 0.005 level. Again, this won't be used in the compensation filter.
Here's the characterization data and fit results for S1100122 , which -- per LHO:85981, LHO:85980 and after 2025-07-25, has been assigned to TMSX M1's F1F2F3LF OSEMs (Fil refers to this as just TMSX F1F2F3LF above). The data was taken per methods described in T080062-v3. The data was processed and fit using ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ plotresponse_S1100122_TMSX_M1_F1F2F3LF_20250724.m Explicitly, the fit to the whitening stage zero and pole, the transimpedance feedback resistor, and foton design string are Optic Stage Serial_Number Channel_Number OSEM_Name Zero_Pole_Hz R_TIA_kOhm Foton_Design TMSX M1 S1100122 CH1 F1 0.0962:5.26 120 zpk([5.26],[0.0962],1,"n") CH2 F2 0.0971:5.31 120 zpk([5.31],[0.0971],1,"n") CH3 F3 0.0957:5.24 120 zpk([5.24],[0.0957],1,"n") CH4 LF 0.0951:5.20 120 zpk([5.20],[0.0951],1,"n") The attached plot and machine readable .txt file version of the above table are also found in ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ As LHO:85626 and the above LHO:86028 discusses, R_TIA_kOhm is the default 120 kOhm.
Here's the characterization data and fit results for S1100058 , assigned to TMSX M1's RTSD OSEMs and CH3CH4 are not connected to any OSEM in-vacuum, hence the "xxxx" place holders (Fil refers to this as just TMSX RTSD above). The data was taken per methods described in T080062-v3. The data was processed and fit using ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ plotresponse_S1100058_TMSX_M1_RTSDxxxx_20250708.m Explicitly, the fit to the whitening stage zero and pole, the transimpedance feedback resistor, and foton design string are Optic Stage Serial_Number Channel_Number OSEM_Name Zero_Pole_Hz R_TIA_kOhm Foton_Design TMSX M1 S1100058 CH1 RT 0.0939:5.11 121 zpk([5.11],[0.0939],1,"n") CH2 SD 0.0960:5.25 120 zpk([5.25],[0.0960],1,"n") CH3 xx 0.0955:5.23 120 zpk([5.23],[0.0955],1,"n") CH4 xx 0.0961:5.25 120 zpk([5.25],[0.0961],1,"n") The attached plot and machine readable .txt file version of the above table are also found in ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ As LHO:85626 and the above LHO:86028 discusses, R_TIA_kOhm is (mostly) the default 120 kOhm, save for CH1.
Here's the characterization data and fit results for S1100071 , assigned to MC2 M1's T1T2T3LF OSEMs (Fil refers to this as just MC2 T1T2T3LF above). The data was taken per methods described in T080062-v3. The data was processed and fit using ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ plotresponse_S1100071_MC2_M1_T1T2T3LF_20250710.m Explicitly, the fit to the whitening stage zero and pole, the transimpedance feedback resistor, and foton design string are Optic Stage Serial_Number Channel_Number OSEM_Name Zero_Pole_Hz R_TIA_kOhm Foton_Design MC2 M1 S1100071 CH1 T1 0.0977:5.34 120 zpk([5.34],[0.0977],1,"n") CH2 T2 0.0956:5.23 120 zpk([5.23],[0.0956],1,"n") CH3 T3 0.0948:5.18 120 zpk([5.18],[0.0948],1,"n") CH4 LF 0.0958:5.22 120 zpk([5.22],[0.0958],1,"n") The attached plot and machine readable .txt file version of the above table are also found in ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ As LHO:85626 and the above LHO:86028 discusses, R_TIA_kOhm is the default 120 kOhm.
Here's the characterization data and fit results for S1100147 , assigned to MC2/PR2 M1's RTSD/T1T2 OSEMs (Fil refers to this as just MC2/PR2 RTSD/T1T2 above). The data was taken per methods described in T080062-v3. The data was processed and fit using ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ plotresponse_S1100147_MC2PR2_M1_RTSDT1T2_20250710.m Explicitly, the fit to the whitening stage zero and pole, the transimpedance feedback resistor, and foton design string are Optic Stage Serial_Number Channel_Number OSEM_Name Zero_Pole_Hz R_TIA_kOhm Foton_Design MC2 M1 S1100147 CH1 RT 0.0975:5.33 120 zpk([5.33],[0.0975],1,"n") MC2 M1 CH2 SD 0.0947:5.18 120 zpk([5.18],[0.0947],1,"n") PR2 M1 CH3 T1 0.0969:5.29 120 zpk([5.29],[0.0969],1,"n") PR2 M1 CH4 T2 0.0962:5.25 120 zpk([5.25],[0.0962],1,"n") The attached plot and machine readable .txt file version of the above table are also found in ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ As LHO:85626 and the above LHO:86028 discusses, R_TIA_kOhm is the default 120 kOhm.
Here's the characterization data and fit results for S1100121 , assigned to PR2 M1's T3LFRTSD OSEMs (Fil refers to this as just PR2 T3LFRTSD above). The data was taken per methods described in T080062-v3. The data was processed and fit using ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ plotresponse_S1100121_PR2_M1_T3LFRTSD_20250710.m Explicitly, the fit to the whitening stage zero and pole, the transimpedance feedback resistor, and foton design string are Optic Stage Serial_Number Channel_Number OSEM_Name Zero_Pole_Hz R_TIA_kOhm Foton_Design PR2 M1 S1100121 CH1 T3 0.0979:5.37 120 zpk([5.37],[0.0979],1,"n") CH2 LF 0.0967:5.29 120 zpk([5.29],[0.0967],1,"n") CH3 RT 0.0958:5.24 120 zpk([5.24],[0.0958],1,"n") CH4 SD 0.0969:5.31 120 zpk([5.31],[0.0969],1,"n") The attached plot and machine readable .txt file version of the above table are also found in ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/ As LHO:85626 and the above LHO:86028 discusses, R_TIA_kOhm is the default 120 kOhm.
I wrote this state at the end of 2023, to automate the relocking of the PLL through turning on the Beckoff autolocker and inputting crystal frequency values to search around. These frequencies it uses to search are assuming the values will be close to zero, so it assumes there isn't an offset alog81425.
We've been going into this fault state more often recently. This state is more of a band-aid for this issue than an actual fix to whatever's happening with the PLLs. ALS-Y sees this issue more frequently than ALS-X, each arm is locking at a different frequency these days, around 0 Hz for Xarm and around 100 for Yarm. Yarm seems more dynamic than Xarm for its' frequency, it has been changing more than Xarm over the past year.
I've updated the code today to use a dictionary with a list for each arm from the single list it was using so hopefully it will make it a little faster.
I'm writing some code with Tonys' statecounter to see exactly how many times we are going into this state for each arm over the past months, and years.
This morning I performed an on-table alignment of the FSS RefCav beam, since yesterday's T.O.O. remote alignment tweak did not get the cavity transmission back above 0.8 V. As usual, I began with a power budget of the FSS beam, and left the ISS ON to keep the power in the FSS path stable:
Immediately it looks like the beam alignment through the AOM in its second pass is way off, but I've never seen the double pass diffraction efficiency this low so I decided to check alignment through the components in the beam path from the AOM to the RefCav before I started making adjustments. Sure enough, the beam was being clipped by the iris that sits between M22 and L11 (this iris block the undesired orders output from the AOM). I opened the iris and measured the power again, this is the number in parenthesis in the above bullets. So the diffraction efficiencies look around normal, but the beam was not well aligned to the iris. This was also seen in the EOM, as it was off alignment as well (but not enough that it was clipping the beam). I went ahead and slightly adjusted the AOM to maximize the single pass diffraction efficiency, and M21 to maximize the double pass diffraction efficiency, with the following results:
At this point, I adjusted the iris position to center it horizontally, and then adjusted M22 to get the beam a bit better centered vertically (iris is on a fixed mount with no vertical adjustment, and I didn't want to go too far and cause problems downstream; not super important that the beam be centered, as the iris is left open enough to pass the desired beam while blocked the others). This done, I opened the iris just enough to let the desired beam pass while still blocking the others. The EOM alignment was adjusted until the beam was centered on both the input and output EOM apertures; I measured 137.3 mW transmitted through the EOM, so free of clipping (the slight difference in double pass AOM Out and EOM Out is normal, the power meter never reads exactly the same). I then manually adjusted the picomotor equipped mounts (M32 and M47) to recenter the beam on the front and back of the RefCav input iris, then locked the RefCav. It locked without issue, so I proceeded to use the picomotors to fine tune the beam alignment into the RefCav.
To end the work in the enclosure I unlocked the RefCav, aligned the reflected beam onto the RFPD, then relocked the RefCav and calculated the visibility:
I then turned the ISS OFF (so it's not actuating on the beam power while the enclosure is returning to thermal equilibrium after the incursion), cleaned up equipment I had used, placed the enclosure into Science Mode, and left the LVEA. I checked on the PSL after about 45 minutes and things appeared to have settled out, so I did one final remote beam alignment of both the PMC (to account for any alignment changes during the incursion) and the RefCav. The PMC alignment was done with the ISS OFF, I then turned the ISS ON (RefSignal of -1.99 V, diffracted power moving between ~3.6% and ~4.0%) to record the final PMC Trans and Refl values and tweak the RefCav alignment. Results:
This ended the RefCav tune up for today. I'm not sure why the iris was clipping the beam, I have not seen that in the time I've been working on the PSL. Best guess I have is drift of mirror M22 due to slow temperature changes, since the diffraction efficiencies of the AOM were still pretty good and this is the only mirror between the AOM and the iris (could also be the PBS cube PBS01, but I don't think so as there was not an increase in the power of the rejected polarization beam). We will continue to monitor this as we usually do, but things are in decent shape right now. This closes LHO WP 12683.
This morning I used a new method of testing airflow and found one power supply in the corner that we missed with thermal testing.
Mezzanine:
C5-U30-RHS Stuck Fan, -24V Digital, S1201957. Current draw is <1A, no overheating detected, it could have been like this for a while.
This supply services H1-SUS-R5 ISC SC Digital. This is paired with the +24V in this rack.
All remaining supplies, good temperature, good airflow, no oscillations.
EX:
All supplies, good temperature, good airflow, no oscillations.
EY:
All supplies, good temperature, good airflow, no oscillations.
Looks like there is a PD Amplifier (D1301017) and an ESD Driver (D1600092) being powered by this +/- 24V supply set.
Tue Jul 15 10:07:36 2025 INFO: Fill completed in 7min 32secs
Gerardo confirmed a good fill curbside.
This morning, I completed the quarterly maintenance of the air handler at the FCES. There were no deficiencies noted. I also completed the thermal imaging of the circuit breaker panels at the end stations. Similarly, there were no deficiencies noted. At both end stations, the panels dedicated to CDS equipment had breakers that showed slightly elevated temperatures, but this is normal. No breakers were observed to be over 30 C.
TITLE: 07/15 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Preventive Maintenance
OUTGOING OPERATOR: Ibrahim
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 15mph Gusts, 9mph 3min avg
Primary useism: 0.02 μm/s
Secondary useism: 0.14 μm/s
QUICK SUMMARY: We've only been at low noise for 20 min, but magnetic injections are running now. Maintenance day today.
Maintenance was delayed by 1 hour this day due to a Fermi GRB notice (E581020) that we received on site a few minutes before 1500UTC. We were not in Observing at the time, but we were in a low noise state. I brought us back into observing at 1510UTC where we stayed until one hour after the initial BRD notice.
I previously noted a glitch about 30 seconds before lockloss in LOWNOISE ASC, 85685. However, we had two more locklosses from this state last night and I do not see such a glitch so that is a random coincidence. One of those locklosses appears to be caused by an earthquake. However, since 6/11, we have had 9 locklosses in this state that occurred exactly 47 seconds into the state, which seems suspicious, one of those occurred last night, and the lockloss with the glitch was the same.
This seems to be coincident with the engagement of a few DHARD P filters:
2025-07-14_14:26:54.641531Z ISC_LOCK executing state: LOWNOISE_ASC (522)
2025-07-14_14:26:54.642230Z ISC_LOCK [LOWNOISE_ASC.enter]
2025-07-14_14:26:54.655894Z ISC_LOCK [LOWNOISE_ASC.main] ezca: H1:ASC-ADS_PIT3_OSC_CLKGAIN => 300
2025-07-14_14:26:54.656325Z ISC_LOCK [LOWNOISE_ASC.main] ezca: H1:ASC-ADS_PIT4_OSC_CLKGAIN => 300
2025-07-14_14:26:54.656732Z ISC_LOCK [LOWNOISE_ASC.main] ezca: H1:ASC-ADS_PIT5_OSC_CLKGAIN => 300
2025-07-14_14:26:54.657043Z ISC_LOCK [LOWNOISE_ASC.main] ezca: H1:ASC-ADS_YAW3_OSC_CLKGAIN => 300
2025-07-14_14:26:54.657438Z ISC_LOCK [LOWNOISE_ASC.main] ezca: H1:ASC-ADS_YAW4_OSC_CLKGAIN => 300
2025-07-14_14:26:54.657892Z ISC_LOCK [LOWNOISE_ASC.main] ezca: H1:ASC-ADS_YAW5_OSC_CLKGAIN => 300
2025-07-14_14:26:54.658134Z ISC_LOCK [LOWNOISE_ASC.main] timer['LoopShapeRamp'] = 5
2025-07-14_14:26:54.658367Z ISC_LOCK [LOWNOISE_ASC.main] timer['pwr'] = 0.125
2025-07-14_14:26:54.783581Z ISC_LOCK [LOWNOISE_ASC.run] timer['pwr'] done
2025-07-14_14:26:59.658298Z ISC_LOCK [LOWNOISE_ASC.run] timer['LoopShapeRamp'] done
2025-07-14_14:26:59.719537Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-CHARD_Y_GAIN => 200
2025-07-14_14:26:59.720456Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-CHARD_Y_SW1 => 256
2025-07-14_14:26:59.846249Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-CHARD_Y_SW2 => 20
2025-07-14_14:26:59.971686Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-CHARD_Y => ON: FM3, FM8, FM9
2025-07-14_14:26:59.972384Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-DHARD_Y_SW1 => 5392
2025-07-14_14:27:00.098073Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-DHARD_Y_SW2 => 4
2025-07-14_14:27:00.223528Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-DHARD_Y => ON: FM1, FM3, FM4, FM5, FM8
2025-07-14_14:27:00.224135Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-CSOFT_P_SMOOTH_ENABLE => 0
2025-07-14_14:27:00.224497Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-CSOFT_Y_SMOOTH_ENABLE => 0
2025-07-14_14:27:00.224868Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-DSOFT_P_SMOOTH_ENABLE => 0
2025-07-14_14:27:00.225188Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-DSOFT_Y_SMOOTH_ENABLE => 0
2025-07-14_14:27:00.225433Z ISC_LOCK [LOWNOISE_ASC.run] timer['LoopShapeRamp'] = 10
2025-07-14_14:27:10.225728Z ISC_LOCK [LOWNOISE_ASC.run] timer['LoopShapeRamp'] done
2025-07-14_14:27:10.281803Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-CHARD_P_TRAMP => 5
2025-07-14_14:27:10.408120Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-CHARD_P_SW2 => 16
2025-07-14_14:27:10.533563Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-CHARD_P => OFF: FM9
2025-07-14_14:27:10.534285Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-CHARD_P_SW1 => 256
2025-07-14_14:27:10.660088Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-CHARD_P_SW2 => 4
2025-07-14_14:27:10.785453Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-CHARD_P => ON: FM3, FM8
2025-07-14_14:27:10.786315Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-CHARD_P_GAIN => 208
2025-07-14_14:27:10.786535Z ISC_LOCK [LOWNOISE_ASC.run] timer['LoopShapeRamp'] = 5
2025-07-14_14:27:15.786858Z ISC_LOCK [LOWNOISE_ASC.run] timer['LoopShapeRamp'] done
2025-07-14_14:27:15.847152Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-DSOFT_Y_TRAMP => 5
2025-07-14_14:27:15.847580Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-DSOFT_Y_GAIN => 5
2025-07-14_14:27:15.848666Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-DSOFT_P_GAIN => 5
2025-07-14_14:27:15.848917Z ISC_LOCK [LOWNOISE_ASC.run] timer['LoopShapeRamp'] = 5
2025-07-14_14:27:20.849050Z ISC_LOCK [LOWNOISE_ASC.run] timer['LoopShapeRamp'] done
2025-07-14_14:27:20.906577Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:SUS-ITMX_M0_DAMP_Y_TRAMP => 10
2025-07-14_14:27:20.907206Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:SUS-ETMX_M0_DAMP_Y_TRAMP => 10
2025-07-14_14:27:20.907700Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:SUS-ITMY_M0_DAMP_Y_TRAMP => 10
2025-07-14_14:27:20.908422Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:SUS-ITMX_M0_DAMP_Y_GAIN => -0.5
2025-07-14_14:27:20.908830Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:SUS-ETMX_M0_DAMP_Y_GAIN => -0.5
2025-07-14_14:27:20.909148Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:SUS-ITMY_M0_DAMP_Y_GAIN => -0.5
2025-07-14_14:27:20.909562Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:SUS-ETMY_M0_DAMP_Y_GAIN => -0.5
2025-07-14_14:27:20.909789Z ISC_LOCK [LOWNOISE_ASC.run] timer['LoopShapeRamp'] = 10
2025-07-14_14:27:30.910055Z ISC_LOCK [LOWNOISE_ASC.run] timer['LoopShapeRamp'] done
2025-07-14_14:27:30.968166Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:SUS-SR2_M1_DAMP_P_GAIN => -0.2
2025-07-14_14:27:30.968527Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:SUS-SR2_M1_DAMP_Y_GAIN => -0.2
2025-07-14_14:27:30.968806Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:SUS-SR2_M1_DAMP_L_GAIN => -0.2
2025-07-14_14:27:30.969073Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:SUS-SR2_M1_DAMP_R_GAIN => -0.2
2025-07-14_14:27:30.969343Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:SUS-SR2_M1_DAMP_T_GAIN => -0.2
2025-07-14_14:27:30.969606Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:SUS-SR2_M1_DAMP_V_GAIN => -0.2
2025-07-14_14:27:30.969838Z ISC_LOCK [LOWNOISE_ASC.run] timer['LoopShapeRamp'] = 10
2025-07-14_14:27:40.970003Z ISC_LOCK [LOWNOISE_ASC.run] timer['LoopShapeRamp'] done
2025-07-14_14:27:40.972085Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-DHARD_P_SW1 => 1024
2025-07-14_14:27:41.097962Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-DHARD_P_SW2 => 4
2025-07-14_14:27:41.223313Z ISC_LOCK [LOWNOISE_ASC.run] ezca: H1:ASC-DHARD_P => ON: FM4, FM8
2025-07-14_14:27:41.223637Z ISC_LOCK [LOWNOISE_ASC.run] timer['LoopShapeRamp'] = 10
2025-07-14_14:27:41.593743Z ISC_LOCK [LOWNOISE_ASC.run] Unstalling IMC_LOCK
2025-07-14_14:27:41.765955Z ISC_LOCK JUMP target: LOCKLOSS
I will take a look and see if there is anything unstable about these filters. Whatever is occurring seems to be too fast to be seen in the ASC signals themselves, and at first glance I don't see anything strange in the suspension channels either.
DHARD FM4 is engaged with a 10 second ramp- this is a change I made on 6/11: 84973 because we had lost lock on that day twice in the same spot. Two of the locklosses at 47 seconds occurred before that change. Then, later that day on 6/11 I reengaged a boost in DHARD P, which only has a 5 second ramp, 84980. Engaging that boost shouldn't be unstable, but maybe something bas occurrs when they ramp at different times. I'm lengthing the ramp to 10 seconds.
We had another lockloss from this state at the 00:47 mark last night, 1436615757 so I'm not sure this fixed the problem.
However, the lockloss was proceeded by a glitch about 30 seconds before, like another lockloss I noticed in this state. This could be coincidence again, but it's looking a little suspicious!
The glitch appears to be occuring due to the CHARD P change. We ramp a boost off with 2 seconds, and a new shaping and low pass on with 2 seconds, and then change the gain with 5 seconds. Looking at the step response of the shaping and lowpass filter, this ramp should probably be 10 seconds, and the gain also 10 seconds to match. I will keep the boost at 2 seconds to ramp off though. I increased the wait timer to 10 seconds to match this ramping. Model and guardian changes saved and loaded.
I am still not sure what is going on with DHARD P, but as a test I've now separated the low pass and loop shape from the engagement of the boost, since we know those individually are stable to engage. We now engage FM4 with a 10 second ramp and wait time, then engage FM8 with a 5 second ramp and wait time. I edited the ramps and gaurdian code to do so, svaed and loaded. This is kind of annoying, but it might help me debug what's going wrong here.
I watched the signals during lownoise ASC, and this time I saw no glitch in CHARD during its lownoise transition. However, I saw a glitch when the DHARD P FM4 filter was engaged, and no glitch when FM8 was engaged. Maybe the ramp of FM4 should be even longer than 10 seconds. I increased the filter ramp to 15 seconds and increased the guardian wait timer to match. Both changes saved and loaded.
We haven't had a lockloss in this state since this fix (but we've had plenty of locks), so I am going to declare this problem fixed!
Randy moved the 3IFO ISS PD array (S1202968) crate from MY storage to the OSB yesterday (WP). I opened the crate, moved the transport/storage container to the vacuum lab and optics lab to inspect. It was in a good shape except that some upgrade parts weren't there. Since I'm already forgetting what happened to other units, here's the summary.
First about parts.
Next, the summary per unit.
Here's the thing about the PD array plate D1300322 (see attached). The updated version has a wider 100deg conical bore for larger beam clearance because it was found at some point (ECR E1400231) that the clearance was too small for the original bore and the reflection of some PDs will hit the bore wall at an glazing angle instead of hitting the beam dump. It's also easy to imagine that if you fiddle with the alignment for the production unit in chamber, INPUT light on some PDs will hit the bore wall first before hitting the PD surface.
We have the blue glass beam dumps for the S1202966 unit, they just need cleaned - location is sitting on top of the unit in the Optics lab.
I have found a bag with a label "Dirty Assy - not in ISC - single parts w/ s/n's in ICS". Inside the bag was an assembly that is a combination of upgrades and obsolete parts.
I'm going to send the upgrade parts to elevate the QPD position to C/B. In addition, I went through all of the boxes we know are somehow related to ISS 2nd loop (again) and found some unused blue glasses. This means that we have enough parts to produce 3 spares if we have to (though it would be a lot of work).
Here's the inventory list of the 2nd loop spare parts as of now: https://dcc.ligo.org/LIGO-E2500191
(Jordan V., Gerardo M.)
Today we replaced the MKS gauge at FC-C-1, this is the first 6 way cross inside the filter cavity tube enclosure, we installed serial number 390F00490, twice, yes two times. It turns out that the flange has some scratches on the knife edge, and it was not going to seal regardless of the effort that we put into it. Once the gauge was removed the scratches transferred to the copper gasket. We replaced it with serial number 390F00495, this one seems to be doing good. New conflat was leak tested and no leak was detectable above 2.42e-10 torr*l/sec.
The old gauge serial number is 390F00406 with a date code of June 2021.
Additional pictures of the knife edge damage/dirty flange from manufacturer.
More photos of the MKS390 gauge due to new found features.
We found some features internal to the gauge, see attached photos, maybe when welding the conflat to the gauge body they did not use shielding gas internal to the gauge.
Future reference, we did a test on the gauge with an annealed copper gasket, no leaks detected above the 1.0e-10 torr*l/sec. So, if this gauge is deemed good we can use it, contacting vendor with lots of questions. Serial number 390F00495 is for the featured gauge on attached photos.
For clarification the serial number of the "dirty" gauge is 390F00490 and it is getting returned to the vendor.
The gauge installed and working on FC-C-1 is serial number 390F00495.
