Displaying reports 10481-10500 of 84760.Go to page Start 521 522 523 524 525 526 527 528 529 End
Reports until 19:13, Monday 18 March 2024
H1 DetChar
gabriele.vajente@LIGO.ORG - posted 19:13, Monday 18 March 2024 (76505)
Peaks in DARM between 20 and 40 Hz

The bump of noise in DARM around 30 Hz is mostly a forest of peaks. One of them (33.43 Hz) is actually a calibration line. For the others, I looked at coherence with corner suspension optical levers and witness sensors. Some of the peaks shos enough coherence to indicate that maybe the peak is due to motion of that suspension

Frequency Suspension
25.19   
26.53   BS / PR3
27.04   BS / PR3 / SR3
27.42  
27.50   
27.72   
28.22   
29.50   PR3 / SR3
29.97   PR3
32.31   
33.33   
33.43   
35.22   PR2
35.71   
39.80   PR3 SR3

Here's a full table of coherence

  25.19 26.53 27.04 27.42 27.50 27.72 28.22 29.50 29.97 32.31 33.33 33.43 35.22 35.71 39.80
H1:SUS-BS_M3_OPLEV_PIT_OUT_DQ 0.019 0.231 0.290 0.008 0.009 0.001 0.003 0.164 0.003 0.028 0.008 0.039 0.123 0.020 0.024
H1:SUS-BS_M3_OPLEV_YAW_OUT_DQ 0.004 0.201 0.304 0.007 0.003 0.003 0.040 0.138 0.022 0.018 0.008 0.012 0.182 0.047 0.118
H1:SUS-PRM_M3_WIT_P_DQ 0.003 0.013 0.020 0.003 0.024 0.001 0.013 0.121 0.042 0.005 0.001 0.001 0.040 0.107 0.001
H1:SUS-PRM_M3_WIT_Y_DQ 0.003 0.017 0.002 0.008 0.014 0.021 0.049 0.001 0.008 0.016 0.033 0.021 0.009 0.007 0.006
H1:SUS-PR2_M3_WIT_P_DQ 0.001 0.002 0.032 0.002 0.021 0.031 0.023 0.013 0.041 0.023 0.013 0.011 0.010 0.013 0.043
H1:SUS-PR2_M3_WIT_Y_DQ 0.004 0.014 0.054 0.006 0.035 0.023 0.005 0.045 0.074 0.002 0.005 0.004 0.020 0.093 0.005
H1:SUS-PR3_M3_OPLEV_PIT_OUT_DQ 0.023 0.257 0.297 0.003 0.033 0.007 0.005 0.166 0.017 0.031 0.001 0.004 0.188 0.007 0.165
H1:SUS-PR3_M3_OPLEV_YAW_OUT_DQ 0.002 0.258 0.297 0.003 0.059 0.005 0.002 0.163 0.005 0.016 0.004 0.002 0.171 0.038 0.109
H1:SUS-PR3_M3_WIT_P_DQ 0.026 0.051 0.005 0.022 0.017 0.035 0.025 0.065 0.365 0.005 0.001 0.028 0.070 0.039 0.021
H1:SUS-PR3_M3_WIT_Y_DQ 0.064 0.072 0.030 0.000 0.020 0.001 0.000 0.052 0.772 0.036 0.079 0.042 0.001 0.353 0.005
H1:SUS-SRM_M3_WIT_P_DQ 0.028 0.049 0.034 0.002 0.001 0.008 0.024 0.049 0.006 0.009 0.011 0.028 0.016 0.001 0.034
H1:SUS-SRM_M3_WIT_Y_DQ 0.006 0.029 0.015 0.059 0.011 0.020 0.022 0.015 0.006 0.029 0.046 0.007 0.003 0.001 0.020
H1:SUS-SR2_M3_WIT_P_DQ 0.004 0.002 0.008 0.006 0.014 0.005 0.054 0.013 0.540 0.008 0.001 0.014 0.012 0.121 0.008
H1:SUS-SR2_M3_WIT_Y_DQ 0.013 0.008 0.039 0.029 0.028 0.010 0.010 0.003 0.521 0.004 0.008 0.003 0.068 0.153 0.008
H1:SUS-SR3_M3_OPLEV_PIT_OUT_DQ 0.014 0.165 0.287 0.006 0.030 0.001 0.001 0.169 0.012 0.009 0.012 0.012 0.145 0.008 0.079
H1:SUS-SR3_M3_OPLEV_YAW_OUT_DQ 0.029 0.133 0.290 0.007 0.040 0.003 0.001 0.173 0.013 0.010 0.008 0.005 0.020 0.006 0.175
H1:SUS-SR3_M3_WIT_P_DQ 0.007 0.002 0.002 0.013 0.011 0.017 0.015 0.046 0.005 0.026 0.007 0.028 0.008 0.068 0.011
H1:SUS-SR3_M3_WIT_Y_DQ 0.092 0.005 0.023 0.014 0.000 0.010 0.021 0.022 0.003 0.000 0.007 0.009 0.008 0.013 0.022
H1:SUS-MC1_M3_WIT_P_DQ 0.031 0.032 0.016 0.005 0.012 0.025 0.003 0.020 0.658 0.003 0.006 0.001 0.042 0.125 0.015
H1:SUS-MC1_M3_WIT_Y_DQ 0.004 0.000 0.009 0.013 0.014 0.004 0.057 0.111 0.124 0.017 0.020 0.012 0.047 0.034 0.041
H1:SUS-MC2_M3_WIT_P_DQ 0.012 0.044 0.016 0.005 0.004 0.016 0.011 0.008 0.061 0.002 0.015 0.028 0.039 0.005 0.036
H1:SUS-MC2_M3_WIT_Y_DQ 0.005 0.009 0.003 0.006 0.024 0.012 0.002 0.012 0.082 0.032 0.058 0.034 0.037 0.029 0.041
H1:SUS-MC3_M3_WIT_P_DQ 0.010 0.014 0.039 0.015 0.025 0.043 0.032 0.008 0.015 0.003 0.003 0.009 0.008 0.018 0.003
H1:SUS-MC3_M3_WIT_Y_DQ 0.003 0.047 0.044 0.009 0.043 0.024 0.004 0.095 0.006 0.049 0.004 0.027 0.015 0.008 0.001
Images attached to this report
H1 SQZ
naoki.aritomi@LIGO.ORG - posted 18:12, Monday 18 March 2024 - last comment - 14:15, Tuesday 26 March 2024(76503)
Old FC2 M1 offload filter in INIT state of SQZ_FC guardian

Evan, Naoki, Nutsinee, Camilla

Today Sheila added nodes.set_managed() in INIT state of SQZ_FC guardian and let SQZ_FC guardian go through the INIT state. However, the FC2 M1 offload filter in the INIT state was old filter setting in 68914, which caused GR_SUS_LOCKING failure. We reverted it as shown in the attachment and updated the FC2 M1 offload filter in INIT state.

Images attached to this report
Comments related to this report
nutsinee.kijbunchoo@LIGO.ORG - 23:21, Monday 18 March 2024 (76510)
Link

Attached a screen shot of the old (wrong) settings on top, correct one at the bottom.

Images attached to this comment
naoki.aritomi@LIGO.ORG - 14:15, Tuesday 26 March 2024 (76722)
Link

In 76503, the limiter for FC2 M1 was not in INIT state of SQZ_FC guardian, but we added the limiter.

Images attached to this comment
H1 ISC (DetChar, ISC)
gabriele.vajente@LIGO.ORG - posted 17:17, Monday 18 March 2024 (76501)
Updated comparison O4a and now

This is an update of the plot in 76372: the high frequency (above 2 kHz) now lines up with the O4a level, but the noise between 40 and 1000 Hz is still larger now than in O4a, although a bit better than a week ago.

The first plot is done with GDS-CALIB_CLEAN: the jitter subtraction is still doing a decent job, even though it was tuned for O4a.

The second plot is done with GDS-CALIB_NOLINES, and shows the jitter peaks in all cases. There is still the same difference between now and then. So jitter is not enough to explain the lowest range we have now.

Images attached to this report
H1 ISC (SQZ)
jennifer.wright@LIGO.ORG - posted 17:17, Monday 18 March 2024 - last comment - 13:40, Thursday 21 March 2024(76500)
Updated ASC-A_DC_YAW_OFFSET

Updated ASC-AS_A_DC_YAW_OFFSET to be -0.15 instead of OFF at 00:09:36 UTC as even though this change has now been put in the guardian we have not lost lock since this was done by Sheila and so the offset was still off. I checked with the squeezers first.

Images attached to this report
Comments related to this report
louis.dartez@LIGO.ORG - 17:27, Monday 18 March 2024 (76502)
Link 

just noting for our future selves: Sheila updated the guardian in LHO:76488.
jennifer.wright@LIGO.ORG - 19:16, Monday 18 March 2024 (76504)
Link

Ibrahim, Jennie W

I analysed the DARM offset step test that Ibrahim ran over the weekend. The contrast defect is now 1.149mW.

See the attached plot for DCPD sum level and circulating power level during the test. DCPD_SUM_OUT is nominally at 40mA before and after the test.  The first attached plot uses the height of two calibration lines on the DCPD and in DARM to track how the DARM optical gain changes with differing power on DCPD sum. The second shows the scaling of DARM optical gain with DARM offset. From this we can see the DARM offset true zero is when the applied offset in OMC-READOUT_X0_OFFSET is 0.608 counts.

Images attached to this comment
Non-image files attached to this comment
H1 ISC (ISC)
jennifer.wright@LIGO.ORG - posted 17:03, Monday 18 March 2024 (76499)
Circulating powers and DARM offset level look similar to 04a

I trended the DARM offset (via checking the fringe offset OMC-READOUT_X0_OFFSET) and the circulating powers in 04 a on Jan 14th and on March 16th post-vent.

The offset and circulating powers have not changed appreciably. The first image is 04a and the second this past Saturday. In both cases the contrast defect was set to give 40mA on DCPD_SUM. The Y cirulating power went up by 2.5W and the X by 2W.

The fringe offset went up by 8.8e-4 counts in that time.

 

Images attached to this report
LHO General
corey.gray@LIGO.ORG - posted 16:12, Monday 18 March 2024 (76496)
Mon EVE Ops Transition

TITLE: 03/18 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: 8mph Gusts, 6mph 5min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.18 μm/s
QUICK SUMMARY:

LHO General
ibrahim.abouelfettouh@LIGO.ORG - posted 16:01, Monday 18 March 2024 (76495)
OPS Day Shift Summary

TITLE: 03/18 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Commissioning
INCOMING OPERATOR: Corey
SHIFT SUMMARY:

IFO is in NLN and COMISSIONING (3hr 45 min lock)

 

16:10(ish) UTC - Began Initial Alignment (couldn’t lock DRMI)

16:30 UTC - Initial Alignment Complete

16:51 UTC - NLN Reached

 

HAM7 Watchdog Story

17:04 UTC - ISI HAM7 WD Tripped - initially assumed due to Nutsinee’s work in LVEA.

17:20 UTC - Nutsinee out - claims to have been very stealthy and to not have caused the trip - her measurements started 1 minute after the trip.

17:35 UTC - HAM7 WD Untripped (was investigating separate issue)

18:36 UTC - HAM7 WD investigation where Jim and Nutsinee attempted to go in and recreate the trip but nothing tripped - interesting..

 

EX ISI WD Trip Weirdness Story

17:12 UTC DCPD Lockloss, appears to have kicked HEPI 200 microns in the horizontal in <4s - somebody should investigate the TIDAL signal.

17:12 UTC - ISI ETMX WD Tripped (Stage 1 and 2) due to the aforementioned HEPI kick (according to Jim) - no vehicles nor personnel there so reason unknown - WD untripped - happened 2s after lockloss and did not CAUSE lockloss.

 

ITMX IOP Down & Reboot Story

17:20 UTC - IOP for ITMX is down dave noticed

17:23 UTC - Fil is taking a look

17:26 UTC - Rebooting SEIB3 rack (adjacent to what Fil was working on so may have been that).

17:33 UTC - IOP rebooted and WDs reset -0 will take a few minutes because HEPI went down and as it goes up, it rings up the T240s - estimated 3-4 minutes until fully untripped and models are back

17:44 UTC- HEPI Back, commencing relock

 

PSL RM (101) Dust Monitor Story

15:30 UTC - Dave restarting dust monitors

17:21 UTC - Dust Monitor 101 not back - not getting data, someone may have forgotten to plug it in according to Dave

18:38 UTC - Ryan S informed of the PSL101 Laser RM dust monitor not receiving data - might go in to investigate tomorrow.

 

19:13 UTC - NLN Reached 

19:13 UTC - Turning on SQZ Angle Adjust


LOG:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            

Start Time System Name Location Lazer_Haz Task Time End
15:11 FAC Karen Optics Lab N Tecnical Cleaning 15:40
15:39 FAC Karen MY N Technical cleaning 16:39
16:08 PCAL Tony/Dripta/Daiki/Francisco Optics Lab N Responsivity measurement 17:30
16:58 SQZ Nutsinee LVEA Local SQZ Test 17:35
17:10 EE Fil CER N BSC Interface Chassis Diagnostics 18:10
17:39 FAC Kim MX N Technical Cleaning 18:39
18:19 SQZ Jim, Nutsinee LVEA N Tripping HAM7 18:36
19:00 PCAL Tony/Francisco Optics Lab N Getting a laser off integrating spheres 20:00
20:49 FAC Tyler EX M Escort to EX 21:49
H1 SQZ (SQZ)
julian.gurs@LIGO.ORG - posted 15:45, Monday 18 March 2024 (76493)
NLG check of the squeezer

Sheila and Julian,

NLG today is 0.1734137/0.0100344 = 17.36, small temperature adjustments were made.

H1 SUS
camilla.compton@LIGO.ORG - posted 15:45, Monday 18 March 2024 - last comment - 10:12, Friday 29 March 2024(76492)
In-lock Charge Measurements Frequencies adjusted

Artem, Camilla

After suggestion from Jeff and Edgard, we've adjusted the In-lock Charge Measurements Frequencies to avoid the 14Hz Roll mode. Measurements were taken last week 76331 and are scheduled for tomorrow AM. We check that results are not effected by this change tomorrow.  Reminder to avoid 11Hz for ETMX 68034.

  Old New
ITMX 14Hz 13Hz
ITMY 15Hz 15Hz
ETMX 13Hz 12Hz
ETMY 12Hz 12Hz

 

Comments related to this report
artem.basalaev@LIGO.ORG - 10:12, Friday 29 March 2024 (76790)
Link 

Before we all forget, just to mention it here: frequencies were reverted back to defaults (left column) before latest attempt of in-lock charge measurements (that caused lock loss 76604). The idea was to repeat "old" setup before trying new one, but we never got the chance before lock loss. Whoever follows up on this, please try to set new drive frequencies (on the right) at some point.
H1 SQZ (SQZ)
julian.gurs@LIGO.ORG - posted 15:02, Monday 18 March 2024 (76486)
New bandstop filters in the squeezed BLRMS for ADF frequencies at 105 Hz and 322 Hz

Sheila and Julian,

have added two new bandstop filters in the squeezed BLRMS for ADF frequencies.

Now we have three: 105 Hz, 322 Hz and 1.3 kHz.

 

105 Hz is in channel 1 and 2 of sum and null: ellip("BandStop",4,1,40,104,106).

322 Hz is in channel 3 of sum and null: ellip("BandStop",4,1,40,321,323).

1.5 kHz is in channel 4 of sum and null.

 

The purpose of that is the optimization of squeezing for lower frequencies.

Images attached to this report
H1 OpsInfo
oli.patane@LIGO.ORG - posted 14:56, Monday 18 March 2024 (76485)
Updated Script for Weekly In-Lock SUS Charge Measurement Analysis FAMIS Task

The Matlab script for the Weekly In-Lock SUS Charge Measurement Analysis FAMIS task, all_single_charge_meas_noplots.m, has been updated to not need us to manually update the gpstime (or the frequency when required) for each data file. The script will now automatically find the latest files in rec_LHO for each quad, double check to make sure they are all from the same set of measurements, and then take those filenames and the frequency listed in the filename and will analyze the data like normal. The procedure on FAMIS will be updated soon, and it is already updated on the wiki: https://awiki.ligo-wa.caltech.edu/wiki/InLock_Charge_Measurements

H1 ISC
sheila.dwyer@LIGO.ORG - posted 14:38, Monday 18 March 2024 - last comment - 00:09, Tuesday 19 March 2024(76488)
Added AS_A yaw offset to guardian

I edited ISC_LOCK LOWNOISE_ASC state to engage the -0.15 offset in AS_A_YAW_DC that was found 76407, I have just loaded it now so it should happen the next time we lock the IFO.

Comments related to this report
louis.dartez@LIGO.ORG - 00:09, Tuesday 19 March 2024 (76512)
Link 

I added a missing counter increment. Corey found that we got stuck here for 20minutes Monday night.

svn revision: 27257
H1 SEI
ryan.short@LIGO.ORG - posted 14:02, Monday 18 March 2024 (76484)
HEPI Pump Trends - Monthly

FAMIS 26464, last checked in alog75972

Trends look very stable, except H1:HPI-PUMP_L0_CONTROL_VOUT has been falling very slightly over the past ~3 weeks.

Images attached to this report
H1 ISC
ibrahim.abouelfettouh@LIGO.ORG - posted 13:47, Monday 18 March 2024 (76483)
Lock Acquisition Time Improvement

Trending Lock Acquisition times from state 10 (DOWN) to state 600 (NOMINAL LOW NOISE) for the last 6 lock acquisitions yields an average of 37.2 mins. That same average for the last 6 lock acquisitions of 04a was 86.8 mins (1 hr and 26 mins). This means that so far, our lock acquisition time seems to have improved by a whole 49.6 minutes, which is also a 230% improvement/time reduction. 

However, it is worth noting that so far, every lock acquisition (bar one or so) since we started relocking to Nominal Low Noise has required an initial alignment, which takes a rough 20-25 minutes. Therefore, from Lockloss to NLN, the last 6 lock acquisitions took 57.2 minutes (assuming 20 mins to initial), which is still a 150% improvement/time reduction. This doesn't count times in O4a where we had that long lock time AND a 20 min initial alignment so it's likely better than 150% on average (which is great!).

Also relevant: Georgia recently pointed out potential redundancies in wait times via the rigorous alog 76398, though none of the changes suggested within have been added yet.

Once H1 is ready for O4b, a similar comparison should/will be made, but this should hopefully foreshadow lock acquisition time improvements.

H1 INS
gabriele.vajente@LIGO.ORG - posted 19:42, Saturday 16 March 2024 - last comment - 11:56, Tuesday 19 March 2024(76462)
OMC alignment

I tested again the OMC aligment with low frequency lines, as in 76335

It looks like there is still some modulation of the DARM line amplitude at 410.x Hz. There is also some effect on the pitch jitter line amplitude, but no effect on the yaw jitter line amplitude.

New offsets that simultaneously make the DARM calibration line maximum and the pitch jitter minimum:

  Old Diff New
A PIT -0.25 -0.07 -0.32
A YAW 0.1 0.1 0.2
B PIT -0.05 -0.05 -0.1
B YAW 0.07 -0.01 -0.03

I put those offsets in. The range dropped. So they are not good. I don't understand why. I reverted them. The range went back. A step in the other directions did not change the range much, but KAPPAC dropped.

Images attached to this report
Comments related to this report
gabriele.vajente@LIGO.ORG - 15:51, Monday 18 March 2024 (76494)
Link

I checked that indeed GDS-CALIB_STRAIN was worse with the alignment offsets that made the range lower

Images attached to this comment
gabriele.vajente@LIGO.ORG - 11:56, Tuesday 19 March 2024 (76520)
Link

Disregard the previous plot, there were two glitches in the data. DARM is slightly worse, but as significantly as thought.

Images attached to this comment
H1 ISC
gabriele.vajente@LIGO.ORG - posted 21:17, Thursday 14 March 2024 - last comment - 16:15, Monday 18 March 2024(76407)
AS_A WFS centering affects the DHARD_Y to DARM coupling

[Louis, Gabriele]

The DHARD_Y to DARM coupling always showed two regimes: a steep coupling below 20-30 Hz, and a flatter coupling above 20-30 Hz. We've been able to change the flatter coupling above 20-30 Hz by changing the ITMT Y2L coefficient.

Today we confirmed a suspicion: the steep low frequency coupling is due to length to angle coupling at the AS WFS. We changed the beam position on the WFS by adding an offset to the WFS centering (H1:ASC-AS_A_DC_YAW_OFFSET) and saw a change in the DHARD_Y to DARM coupling.

A value close to -0.14 gives the minimum coupling below 20 Hz. we now have two independent knobs to minimize the DHARD_Y to DARM coupling at all frequencies.

Incidentally, the higher frequency couping is now lower than yesterday, with the same ITMY Y2L coefficient of -1.65

We did a scan of the AS_A_WFS Y centering from -0.2 to -0.1 in steps of 0.01, an analysis will follow tomorrow:

-0.200: 1394510627 - 1394510727
-0.190: 1394510777 - 1394510877
-0.180: 1394510927 - 1394511027
-0.170: 1394511077 - 1394511177
-0.160: 1394511227 - 1394511327
-0.150: 1394511377 - 1394511477
-0.140: 1394511527 - 1394511627
-0.130: 1394511677 - 1394511777
-0.120: 1394511827 - 1394511928
-0.110: 1394511978 - 1394512078
-0.100: 1394512128 - 1394512228
 0.000: 1394512278 - 1394512378

We are leaving a value of -0.14 in the WFS offset

 

Images attached to this report
Comments related to this report
louis.dartez@LIGO.ORG - 21:57, Thursday 14 March 2024 (76408)
Link 

Attached is a comparison of the DARM sensing function with no AS A centering offset vs an offset of -0.14. 

With an AS A centering offset of -0.14, which we found to be the value that results in the minimum amount of coupling to DARM below 20Hz, the sensing function clearly shows optical spring-like characteristics. This brings to mind a few thoughts: 

1. This supports the idea that coupling from the DHARD loop into DARM has a noticeable effect on the structure seen in the sensing function at low frequencies. We've been wondering about this for some time, so it's nice to finally have a direction to point in.
2. We tend to adjust the src detuning by constantly measuring the sensing function and trying to find an SRC offset that results in a flat sensing function at low frequencies. The fact that DHARD also couples with DARM in such a way that it can affect the shape of the sensing function at low frequencies begs the question: could we be in fact further detuning the src while intending to do the opposite due to confusion caused by the dhard coupling effects?
3. I recall being told that sometimes squeezing gets better with some level of detuning. If our only measure of SRC detuning is from measuring and inspecting the sensing function then this measurement hasn't been clean due to the DHARD coupling. 


lots to think about..
Images attached to this comment
gabriele.vajente@LIGO.ORG - 10:46, Friday 15 March 2024 (76419)
Link

Here's a more detailed analysis of the AS WFC centering steps.

The first plot shows the steps in ASC-AS_A_DC_YAW_OFFSET compared with a DARM spectrogram, during a DHARD_Y injection. The spectrogram shows that there is minimum in the coupling of DHARD_Y to DARM around -0.15 / =0.16.

The second plot shows the transfer function from DHARD_Y to DARM for all values of the offset. A value of -0.15 gives the lowest coherence and the lowest coupling, so that seems to be the optimal value. One can notice how the transfer function phase flips sign as expected when one goes through the minimum coupling.

Images attached to this comment
gabriele.vajente@LIGO.ORG - 11:50, Friday 15 March 2024 (76422)
Link

Changing the AS_A centering offset also moved SR2, SRM and BS.

elenna.capote@LIGO.ORG - 21:38, Friday 15 March 2024 (76451)
Link

I tried stepping the REFl WFS A and B DC offsets in yaw similarly to see if the CHARD Y coupling to DARM would change. In summary, I stepped between -0.2 and 0.2 for both WFS and saw no change.

Method: I set a 30 second ramp on the offsets because the DC centering loops are slow. I stepped first in steps of 0.01, and then 0.02. I injected a broadband CHARD Y injection and measured the transfer function to darm between 10-30 Hz. I saw no change in the coupling while I made these steps.

minhyo.kim@LIGO.ORG - 14:52, Monday 18 March 2024 (76489)
Link

Before checking on the calibration change in DARM and DHARD, I check on the thermalisation effect with the coupling.
I chose long duration locking time (Mar. 16, 05:30:00 UTC ~ 15:30:00 UTC) without centering offset, and selected start, middle (10:30:00 UTC) and end time within the time window.

Three plots are; 1) DARM, 2) DHARD PIT, 3) DHARD YAW.
In addition, I included screenshot of ndscope to confirm the time window.

As the 'end' time data in all plots show different trend compare to the other times, it seems that the thermalisation affects DARM and DHARD.

Images attached to this comment
minhyo.kim@LIGO.ORG - 16:15, Monday 18 March 2024 (76490)
Link

Checked on the calibration lines in DARM and DHARD with centering offset on/off conditions.
To minimize the thermalisation effect, time for the comparison were chosen within short time window.

Figures are; 1) Comparison altogether, 2) DARM comparison, 3) DHARD PIT, 4) DHARD YAW, 5) Screenshot of the ndscope around comparison time.

It can be confirmed that the peaks of calibration lines were same in DARM with and without the centering offset. However, for DHARD, only YAW showed calibration lines, and with different peak magnitude (lower in without offset).

Images attached to this comment
H1 ISC (GRD)
jennifer.wright@LIGO.ORG - posted 12:42, Thursday 07 March 2024 - last comment - 14:35, Monday 18 March 2024(76188)
OMC_LOCK guardian updated

Ryan S, Jennie W, Camilla

Camilla noticed the OMC_LOCK guardian was failing to find the carrier resonance during the ISC_LOCK guardian state.

Ryan discovered this was due to the triplet (1 45MHz peak either side of the carrier) that the OM_LOCK guardian looks for was not being found by scipy.find_peaks() as the carrier resonance are bellow 9 counts which is its threshold. So we changed the 'height' threshold of find_peaks to 7 on line 327 of OMC_LOCK guardian and commited this change.

We also changed the OMC_LOCKED guardian state at line 511 to look for OMC-DCPD_SUM_OUTPUT to be more than 7 instead of 10.

Comments related to this report
jennifer.wright@LIGO.ORG - 12:46, Thursday 07 March 2024 (76189)
Link

I think it is reasonable that we had to make this change as the OMC is probably not well aligned as the OMC scan the other day showed we had a lot of HOM content in the beam.

ryan.short@LIGO.ORG - 14:35, Monday 18 March 2024 (76487)
Link

Since OMC (and overall IFO) alignment has improved, we are now seeing good transmission on the OMC DCPDs as we were in O4a, so I've reverted the above threshold changes in the OMC_LOCK Guardian.

H1 DAQ
daniel.sigg@LIGO.ORG - posted 12:18, Wednesday 07 February 2024 - last comment - 21:53, Tuesday 17 December 2024(75761)
Previous/spare timing master

The previous timing master which was again running out of range on the voltage to the OCXO, see alogs 68000 and  61988, has been retuned using the mechanical adjustment of the OCXO.

Today's readback voltage is at +3.88V. We will keep it running over the next few months to see, if it eventually settles.

Comments related to this report
daniel.sigg@LIGO.ORG - 10:33, Wednesday 21 February 2024 (75912)
Link

Today's readback voltage is at +3.55V.

daniel.sigg@LIGO.ORG - 16:18, Monday 18 March 2024 (76497)
Link

Today's readback voltage is at +3.116V.

daniel.sigg@LIGO.ORG - 15:25, Tuesday 07 May 2024 (77697)
Link

Today's readback voltage is at +1.857V.

daniel.sigg@LIGO.ORG - 15:54, Monday 15 July 2024 (79142)
Link

Today's readback voltage is at +0.951V.

daniel.sigg@LIGO.ORG - 21:53, Tuesday 17 December 2024 (81886)
Link

Today's readback voltage is at -2.511V

Displaying reports 10481-10500 of 84760.Go to page Start 521 522 523 524 525 526 527 528 529 End