Displaying reports 1001-1020 of 83128.Go to page Start 47 48 49 50 51 52 53 54 55 End
Reports until 14:59, Friday 23 May 2025
H1 PSL (PSL)
corey.gray@LIGO.ORG - posted 14:59, Friday 23 May 2025 (84564)
PSL Status Report (FAMIS #26416)

This is for FAMIS #26416.
Laser Status:
    NPRO output power is 1.842W
    AMP1 output power is 70.19W
    AMP2 output power is 140.3W
    NPRO watchdog is GREEN
    AMP1 watchdog is GREEN
    AMP2 watchdog is GREEN
    PDWD watchdog is GREEN

PMC:
    It has been locked 4 days, 6 hr 50 minutes
    Reflected power = 23.09W
    Transmitted power = 105.5W
    PowerSum = 128.6W

FSS:
    It has been locked for 0 days 0 hr and 14 min
    TPD[V] = 0.82V

ISS:
    The diffracted power is around 3.9%
    Last saturation event was 0 days 3 hours and 31 minutes ago


Possible Issues:
    PMC reflected power is high

H1 ISC (EPO, ISC)
corey.gray@LIGO.ORG - posted 14:51, Friday 23 May 2025 (84561)
HAM1 Close-Out Photos

On May 15, 2025, "close-out" photos were taken of everything on the new HAM1 SEI ISI Optics Table a few days before HAM1 was sealted up & pumped down.  Took almost 300 photos/videos (~66Gb)!  These photos/videos have been uploaded to this google drive location:

https://drive.google.com/drive/folders/1w4GwB5H2c7Dgw37FxRgLK0ganJ1nycxs?usp=sharing

Notes:

Images attached to this report
LHO VE
david.barker@LIGO.ORG - posted 10:25, Friday 23 May 2025 (84562)
Fri CP1 Fill

Fri May 23 10:19:34 2025 INFO: Fill completed in 19min 30secs

 

Images attached to this report
LHO General
corey.gray@LIGO.ORG - posted 07:43, Friday 23 May 2025 (84559)
Fri Ops Day Transition

TITLE: 05/23 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
OUTGOING OPERATOR: Ryan C
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 4mph Gusts, 1mph 3min avg
    Primary useism: 0.01 μm/s
    Secondary useism: 0.10 μm/s
QUICK SUMMARY:

Sheila is sorting through the state of alignment which will then lead to continuing ISCT1 alignment work out on the floor.  Mitch and Randy are at EX starting on the wind fence.

LHO VE
janos.csizmazia@LIGO.ORG - posted 17:35, Thursday 22 May 2025 (84556)
Some vacuum troubleshooting - HAM1
Janos

Today morning the pressure in HAM1 rose quite quickly to ~1E-3 Torr. As I was driving to the site, Richard found out that the new Agilent leak checker, which backed the turbo, stopped. So he valved out the turbo via its main gate valve.
After arrival, I valved out the leak checker, valved in the Supersucker cart's Anest Iwata ISP500 pump, and restarted the turbo, then valved it back again. The pressure very quickly dropped to ~7E-6 Torr (roughly where it was before the incident). Since then, everything is nominal.

In the afternoon around 3 pm I valved in IP13 (500 l/s Starcell) to HAM1. The pressure nicely dropped to the low E-6s, however, it started growing. I checked the controller in the MER, and found that it is unable to hold the usual -7000 Volts, in fact, it was around -3000 Volts, and dropping (towards 0). Moreover, I found that the controller's comm cable is not wired properly to CDS, its channel reads IP1/B ion pump. So I valved out the Ion-pump.
With Dave, Fil, Richard, and Patrick we looked into the problem, and we quickly found that the Ion-pump's comm cable physically was not wired in at all.
I quickly plugged the valved out Ion-pump to an IPC mini, which obviously hardly could hold the pressure, but the voltage still slowly converged to -7000 V. After this, I located a spare controller (brand new, identical to the one we used), also attached a bypass connector to the comm outlet, and plugged the Ion pump to this one. It quickly reached the nominal -7000 Volts. (See the new (left) and old, broken down (right) controller on the IP-controller rack in the MER).
Early next week, after (hopefully) a successful leak check on HAM1, the Ion-pump will be valved in permanently. The comm cable wiring will also be finalized later.
Images attached to this report
LHO General
ryan.short@LIGO.ORG - posted 17:33, Thursday 22 May 2025 (84552)
Ops Day Shift Summary

TITLE: 05/22 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY: Another busy day! After some pumpdown troubleshooting this morning, ISCT1 was rolled back into place, its bellows were attached, and beam alignment on the table is ongoing. Cycled ISC_LOCK through DOWN and SDF_REVERT, but ran into an issue where ETM ESD chassis needed to be restarted after the power outage last night. I also ran a quick rotation stage calibration.

LOG:

Start Time System Name Location Lazer_Haz Task Time End
14:58 FAC Kim, Nellie LVEA N Technical cleaning (Nellie out @ 16:00) 17:12
14:59 FAC Chris LVEA N Retrieving parts 15:02
15:21 VAC Janos LVEA N Troubleshooting HAM1 pumpdown 16:01
15:43 SEI Jim LVEA N Locking HAM1 HEPI 15:53
15:55 FAC Richard LVEA N Checks 16:03
16:00 AOS Jeff OptLab N Dropping off parts 16:13
16:07 SEI Mitchell, Randy, Corey EX N Wind fence work 19:19
16:19 ISC Camilla, TJ, RyanC, Oli LVEA N Moving ISCT1 into place 17:04
16:27 FAC Janos, Chris LVEA N Retrieving rigging equipment 16:29
16:59 FAC Richard LVEA N Checks 17:09
17:04 ISC Camilla, TJ LVEA N ISCT1 bellows 17:16
17:16 CDS Fil LVEA N Cabling ISCT1 19:59
18:39 SAF Camilla, TJ LVEA N Looking for RS key 18:47
19:37 VAC Janos LVEA N Checking on HAM1 bellows 19:46
20:03 ISC TJ LVEA YES Transition to Laser HAZARD 20:25
20:59 SEI Corey EX N Wind fence work 21:39
21:06 CAL Tony PCalLab Local   21:14
21:14 ISC Elenna LVEA YES ISCT1 alignment Ongoing
21:16 ISC TJ LVEA YES ISCT1 alignment 23:26
21:34 VAC Janos LVEA - Valve in ion pump to HAM1 22:34
21:40 EE Fil EX N Checking ESD HV chassis 22:09
21:41 EE Marc EY N Checking ESD HV chassis 22:09
22:18 ISC Sheila LVEA YES ISCT1 alignment Ongoing
23:02 ISC Camilla LVEA YES ISCT1 alignment Ongoing
H1 PSL
ryan.short@LIGO.ORG - posted 17:25, Thursday 22 May 2025 - last comment - 17:28, Thursday 22 May 2025(84553)
PSL Rotation Stage Calibration

After ISCT1 alignment worked wrapped up for the day, I ran a calibration sweep of the PSL rotation stage following the steps outlined in alog79596.

The measurement file, new calibration fit, and screenshot of newly accepted SDFs are attached.

  Power in (W) D B (Minimum power angle) C (Minimum power)
Old Values 94.908 1.990 -24.819 0.000
New Values 95.252 1.990 -25.787

0.000

Images attached to this report
Non-image files attached to this report
Comments related to this report
ryan.short@LIGO.ORG - 17:28, Thursday 22 May 2025 (84555)

Interestingly, even after updating the calibration factors and searching for home on the stage, there are still 2.2W into the IMC with a 2.0W request, so this may need revisiting later.

H1 ISC
elenna.capote@LIGO.ORG - posted 17:13, Thursday 22 May 2025 (84554)
ISCT1 table alignment

TJ, Camilla, Sheila, Elenna

We went out to ISCT1 to realign all ALS paths. The baffle align scripts were successfully run for the ITMs and TMS. I moved the BS to improve the MICH alignment. We then misaligned the ITMs and went to the table.

TJ and I were able to find both green beams and the PSL red beam coming in on the periscopes. The PSL ALS beam was mostly hitting the beamdump that Sheila and Betsy had previously put on the path, but was slightly off. TJ moved the upper periscope mirror to center the green beams and the PSL beam. We got everything pretty well placed on the periscope, and then TJ improved the lower periscope green mirror to get each beam aligned onto the prism.

Sheila and I were able to get the beam aligned for the ALS X path and saw it on the camera. We moved the diode around until we got pretty good alignment. Then, I adjusted ETMX by hand to improve both the diode flashes and the camera image. At some point I hit a wall and found that moving TMSX also helped the alignment considerably. Eventually everything was well-aligned enough that I could let the ALSX guardian run through ETM TMS WFS offloaded.

I tried doing the input align with the X arm, but couldn't get LSC TR norm flashes good enough. I had to move PR2 a lot in yaw. I also tried some moves with IM4. Gave up for the day.

Meanwhile, TJ, Camilla, and Sheila touched up the ALS Y path and the PSL ALS path. The Y arm diode and camera are now well enough aligned that we could run the ALS Y guardian.

The PSL path needs more work, and currently the beam is dumped just before the SHG.

H1 ISC
daniel.sigg@LIGO.ORG - posted 15:36, Thursday 22 May 2025 (84551)
ISCT1 cleanup

We removed all cables belonging to the analog cameras as well as a 12V power distribution box. Removed the video feedthrough panel and replaced it with a PEM feedthrough panel that previsouly was mounted on the other side.

We removed the cables associated with the 2 original in-air WFS. Removed the 2 feedthrough panels associated with the WFS.

We de-cabled the Mad City Lab PZT steering mirror, but did not remove it yet.

LHO General (EPO, PEM, SEI)
corey.gray@LIGO.ORG - posted 15:27, Thursday 22 May 2025 (84550)
EX Windy Wind Fence Update For Today

(CoreyG, MitchR, RandyT)

Wind Fence News

Today Location #4 (of6) had fabric panel started it was attached above the middle (so, 3 of 5 horizontal cables were secured to this panel).  The panel was then secured at this stage since the afternoon winds were beginning to pick up.  

At this point we moved to location #5 (of 6) and continued attaching the big/thick horizontal cables (bottom was installed last week, so the remaining 4 were tensioned-up/installed.  

Bee News

After this work was done, several NEW bee swarms were observed along the X-arm as we drove back to the Corner!

(Earlier this week an X-arm bee swarm was observed and a bee person installed a bee hive box; this box seems to be getting populated, but we did see some bees continuing to go into the Beam Tube at this location). 

But today, we saw (3) NEW Swarms at the base of the Beam Tube Enclosure---their swarms appeared within 2hrs!  The bees are entering at the joint between the cement enclosures. Many of the joints have holes in the cauking toward the ground and this is where the swarms were centered; as we drove back to the corner several more of these holes had smaller groups of bees investigating these holes.  Mitch went to notify Richard about the situation when we got back to the Corner Station.

Images attached to this report
H1 DetChar (DetChar)
ansel.neunzert@LIGO.ORG - posted 15:01, Thursday 22 May 2025 (84546)
Line at 1028, 1038, 1048 etc Hz

An apparent 10-Hz comb at 1028, 1038, 1048... Hz was spotted while updating the lines lists. The peaks are right on integer frequencies (to within a single bin in 7200s SFTs).

I took a closer look and found that it's actually a single line jumping around in the spectrum. Anybody recognize this?

The line can also be seen in H1:PEM-CS_MAG_EBAY_LSCRACK_Z_DQ. It seems like it started coupling to DARM after the O4a/b break.

Details:

History of the line in DARM:

Comparison of magnetometer and strain data (y-axis for all plots is frequency; label got cut off for some reason): 

Images attached to this report
H1 SUS (SUS)
edgard.bonilla@LIGO.ORG - posted 14:39, Thursday 22 May 2025 - last comment - 14:52, Thursday 22 May 2025(84548)
Tested the SR3 OSEM calibration [It works!]

Oli, Edgard.

On Tuesday, Oli tested the SR3 OSEM calibration factors mentioned in the comments of [LHO:84296] and summarized in [LHO:84531] and took a new suite of HAM5 ISI to SR3 M1_DAMP transfer functions (the measurements also live in /HLTS/H1/Common/Data/ and are dated for May 21st of 2025). 

The calibration factors from [LHO:84531] (taken on May 7th) featured a seemingly crazy change on the T1 OSEM calibration of 2.4539 x. So we wanted to doublecheck that the numbers actually made sense before proceeding with OSEM estimator work.

The measured SUSPOINT V to M1_DAMP_{ V , R , P } show that the calibration factor was largely correct. 

The first attachment shows the SUSPOINT V to M1_DAMP_{ V , R , P } in measured on May 7th before using the new OSEMINF gains. In it, it can be seen that there is a very clear crouss-coupling from V to R, which is mediated by the T1 OSEM in SR3. Dividing the length-to angle over the length-to-length at 10 Hz to get a sense of the cross-coupling we get 3.3 rad/m for R and 0.65 rad/m for P.

The second attachment shows the SUSPOINT V to M1_DAMP_{ V , R , P } measured on May 21st after using the new OSEMINF gains. The V to R (and to P) improves significantly with the new calibration factors. This is best seen by comparing the relative amplitude of the V to V transfer function (in red) with the V to R (in blue), and the V to P (in green), through which we get 0.4 rad/m for R and 0.1 rad/m for P. Therefore, the apparent cross-coupling has been greatly reduced, which confirms that the T1 factor was likely correct, and we can proceed with the rest of the procedure.

[NOTE: We use relative factors for the comparison, because all OSEMs were miscalibrated by a factor of 1.3-1.4, so directly comparing the amplitudes from may 7th to May 21st would be inaccurate]

These improvements are encouraging enough that we feel comfortable moving forward with the M1 OSEM calibration for SR3. To do so, Oli is hard at work rescaling the gains of the SR3 loops. We will post when that steps is ready

 

 

 

Images attached to this report
Comments related to this report
edgard.bonilla@LIGO.ORG - 14:52, Thursday 22 May 2025 (84549)

As a sidenote, I ran the calibration script from [LHO:84531] on the May 21st HAM5 to SR3 data to see how stable the ISI to OSEM calibration is likely to be.

The TL;DR is that most OSEM gains are estimated to remain almost the same, the only suggested gain change above 1% is the T1 OSEM which is suggested to change by 6%, which is small enough that we will leave it alone for now. These results imply that the calibrations are good enough that they won't change by much on a weekly basis.

We will NOT adjust the SR3 M1 OSEMINF gains again with the values listed below

 

This is the output of the script:

%%%%%%
We have estimated a OSEM calibration of H1 SR3 M1 using HAM5 ST1 drives from 2025-05-21_0000 (UTC).
We fit the response M1_DAMP/HAM5_SUSPOINT between 5 and 15 Hz to get a calibration in [OSEM m]/[GS13 m]

The H1:SUS-SR3_M1_OSEMINF gains at the time of measurement were:
(old) T1: 3.627
(old) T2: 1.396
(old) T3: 0.952
(old) LF: 1.302
(old) RT: 1.087
(old) SD: 1.290

The suggested (calibrated) M1 OSEMINF gains are
(new) T1: 3.435
(new) T2: 1.389
(new) T3: 0.952
(new) LF: 1.296
(new) RT: 1.088
(new) SD: 1.292

To compensate for the OSEM gain changes, we estimate that the H1:SUS-SR3_M1_DAMP loops must be changed by a factors of:
L gain = 1.002 * (old L gain)
T gain = 0.998 * (old T gain)
V gain = 1.029 * (old V gain)
R gain = 1.029 * (old R gain)
P gain = 1.003 * (old P gain)
Y gain = 1.002 * (old Y gain)

This message was generated automatically by OSEM_calibration_SR3.py on 2025-05-22 20:49:42.062366+00:00 UTC
%%%%%%

 

H1 SUS (CDS, SUS)
jeffrey.kissel@LIGO.ORG - posted 14:30, Thursday 22 May 2025 (84547)
Greenlighted sush2b HAM1 Software Watchdog (SWWD)
J. Kissel

Now that PM1, RM1, and RM2 are safely functional on the new ISI HAM1, in the h1iopsush2b front-end model, I've
    - set H1:IOP-SUS_${OPTIC}_DK_BYPASS_TIME to 600 seconds H1:IOP-SEI_HAM1_DK_BYPASS_TIME
    - set H1:IOP-SEI_HAM1_DK_BYPASS_TIME to 999999999 (~1e9) seconds, as is seemingly common in most SWWDs
    - hit RESET on each of the SUS DACKILLs and the SEI DACKILL to arm them
    - initialized the PM1 channels in the safe.snap and accepted and monitored their current values
H1 SUS (ISC)
jeffrey.kissel@LIGO.ORG - posted 14:10, Thursday 22 May 2025 (84545)
PM1 Accepted in h1sushtts safe.snap with settings in the ALIGNED state
J. Kissel, T. Shaffer

In the current O4 paradigm of SDF practice, we've minimized the number of .snap files to track by accepting the settings of some suspension whose setting don't change between "IFO down" and "Observing." That includes SUS RM1 and RM2, which live on the sushtts model -- that also now is home to PM1. RM1 and RM2 are ALIGNED at the moment, with damping loops and alignment offsets ON, and yet their settings do not show up as "different" from the safe.snap. This disagrees with the principle of "safe" but it's how we're doin it. 

As such, I've accepted PM1's settings in the ALIGNED state into the sushtts safe.snap.

Images attached to this report
H1 ISC
camilla.compton@LIGO.ORG - posted 13:36, Thursday 22 May 2025 (84544)
ISCT1 Moved back into Place and Bellows Reattached

TJ, Ryan C, Oli, Camilla. WP#12561

Randy had forklifted ISCT1 just outside of the cleanroom. We pushed ISCT1 back into place and checked it's location and height. Removed yellow VP covers and replaced bellows, then removed guillotines.

H1 SUS (SEI, SUS)
edgard.bonilla@LIGO.ORG - posted 12:34, Thursday 22 May 2025 - last comment - 13:50, Monday 23 June 2025(84531)
M1 SR3 OSEM calibration [revisited]

Oli, Edgard, Jeff, Brian

This post is meant to give a clearer explanation of the work in [LHO:84296] and its many comments. We are trying to find a new set of gains for the M1_OSEMINF filter banks for SR3 to calibrate the OSEMs to be in agreement with the HAM5 GS13s.

To do so, we drive the HAM5 ISI in { X , Y , Z } and record the response of the relevant OSEMs between 5 to 15 Hz.  At these frequencies, the M1 stage of the suspension should start to become inertial, and the M1_DAMP / SUSPOINT response of each individual OSEM should asymptote to -1, because the OSEMs would be measuring their support point on the cage [barring internal dynamics of the cage itself].

To increase the accuracy of the calibration, we use the MATLAB model of the HLTS and use the full extent of the 5-15 Hz data instead of only the asymptotic behavior.

I post here the code used to generate these results. The code requires the new Common/MatlabTools/ExportedModels folder from the SusSVN [LHO:84458]. The detailed results of the calibrations mentioned is shown below.

_____

Images attached to this report
Non-image files attached to this report
Comments related to this report
edgard.bonilla@LIGO.ORG - 17:06, Tuesday 27 May 2025 (84605)SUS

Adding hera a few bits of information that were missing from the original post, together with an updated version of the script.

_______________________________________________________________________

To compensate for the OSEM gain changes, we estimate that the H1:SUS-SR3_M1_DAMP loops must be changed by a factors of:
L gain = 0.743 * (old L gain)
T gain = 0.724 * (old T gain)
V gain = 0.549 * (old V gain)
R gain = 0.549 * (old R gain)
P gain = 0.691 * (old P gain)
Y gain = 0.743 * (old Y gain)

The calibration will change the apparent alignment of the suspension as seen by the at the M1 OSEMs
NOTE: The actual alignment of the suspension will NOT change as a result of the calibration process

The changes are computed as (osem2eul) * gain * inv(osem2eul).
Using the alignments from 2025-05-07_0000 (UTC) as a reference, the new apparent alingments are:

DOF    Previous value     New value       Apparent change
---------------------------------------------------------------------------------
L          -4.3 um                 -2.6 um                     +1.7 um
T          -19.7 um              -14.2 um                 +5.4 um
V          -24.0 um              -8.4 um                   +15.6 um
R          -490.6 urad          -219.3 urad          +271.4 urad
P          -300.2 urad          -203.8 urad          +96.5 urad
Y          -569.3 urad          -422.5 urad          +146.8 urad

Non-image files attached to this comment
edgard.bonilla@LIGO.ORG - 18:21, Tuesday 27 May 2025 (84607)SUS

Here I post the coherence and transfer functions between the excitations of HAM5 in X, Y, and Z to the SUSPOINT degrees of freedom.

The band from 5-10 Hz seems to be low enough amplitude that I think we can claim that the drives are clean enough in the SUSPOINT basis to perform the calibration.

Note that the high coherence between L/T and HAM5_ISO X/Y is expected, since the SR3 euler basis does not perfectly align with the cartesian basis of HAM5.

 

 

Images attached to this comment
jeffrey.kissel@LIGO.ORG - 13:50, Monday 23 June 2025 (85255)
J. Kissel (for O. Patane and E. Bonilla)

Also during this barrage of measurements, Oli and Edgard gathered Open Loop Gain (IN1/IN2), Loop Suppression (IN2/EXC), and Closed Loop Gain (IN1/EXC) tfs under the presence of DAMP_EXC. 

Within the templates mentioned below, there're two data sets.
The "New OSEMINF gains" data is with with the above mentioned
    H1:SUS-SR3_M1_OSEMINF_T1_GAIN  3.627
    H1:SUS-SR3_M1_OSEMINF_T2_GAIN  1.396
    H1:SUS-SR3_M1_OSEMINF_T3_GAIN  1.345
    H1:SUS-SR3_M1_OSEMINF_LF_GAIN  1.719
    H1:SUS-SR3_M1_OSEMINF_RT_GAIN  1.490
    H1:SUS-SR3_M1_OSEMINF_SD_GAIN  1.781

The "OG OSEMINF gains" data is with the OSEMINF gains that have been present throughout O4 (as they were reverted post-measurement) 
    H1:SUS-SR3_M1_OSEMINF_T1_GAIN  1.478
    H1:SUS-SR3_M1_OSEMINF_T2_GAIN  0.942
    H1:SUS-SR3_M1_OSEMINF_T3_GAIN  0.952
    H1:SUS-SR3_M1_OSEMINF_LF_GAIN  1.302
    H1:SUS-SR3_M1_OSEMINF_RT_GAIN  1.087
    H1:SUS-SR3_M1_OSEMINF_SD_GAIN  1.29

The raw .xmls for both these data is 
    /ligo/svncommon/SusSVN/sus/trunk/HLTS/H1/SR3/SAGM1/Data/
        2025-05-21_1800_H1SUSSR3_M1_WhiteNoise_L_0p02to50Hz_OpenLoopGainTF.xml
        2025-05-21_1800_H1SUSSR3_M1_WhiteNoise_P_0p02to50Hz_OpenLoopGainTF.xml
        2025-05-21_1800_H1SUSSR3_M1_WhiteNoise_R_0p02to50Hz_OpenLoopGainTF.xml
        2025-05-21_1800_H1SUSSR3_M1_WhiteNoise_T_0p02to50Hz_OpenLoopGainTF.xml
        2025-05-21_1800_H1SUSSR3_M1_WhiteNoise_V_0p02to50Hz_OpenLoopGainTF.xml
        2025-05-21_1800_H1SUSSR3_M1_WhiteNoise_Y_0p02to50Hz_OpenLoopGainTF.xml

The open loop gain transfer functions (IN1/IN2) have already been exported
    /ligo/svncommon/SusSVN/sus/trunk/HLTS/H1/SR3/SAGM1/Data/
        2025-05-21_1800_H1SUSSR3_M1_WhiteNoise_?_0p02to50Hz_OpenLoopGainTF_tf.txt     << exports of "OG OSEMINF gains" data

        2025-05-21_2000_H1SUSSR3_M1_WhiteNoise_L_0p02to50Hz_OpenLoopGainTF_tf.txt     << exports of "New OSEMINF gains" data

Also, I've exported the loop suppression of the "OG OSEMINF gains" data as
    /ligo/svncommon/SusSVN/sus/trunk/HLTS/H1/SR3/SAGM1/Data/
        2025-05-21_1800_H1SUSSR3_M1_WhiteNoise_?_0p02to50Hz_OLGTF_LoopSuppression_tf.txt     << exports of "OG OSEMINF gains" data
H1 SUS
oli.patane@LIGO.ORG - posted 11:50, Thursday 22 May 2025 (84543)
Closeout transfer functions confirm open questions on RM signs

Jeff, Oli

Looking into (1) from 84462.

Before this vent, although the cable pinouts were flipped for both RMs, the phase for the TFs were at 0. Now that the cables have been flipped (fixed), we are seeing that the closeout transfer functions that I took 84498 are showing that the phase for the RMs is now flipped, at 180. Additionally, both RMs are still needing the damping sign to be +1, instead of the usual -1.

Since there does still seem to be a sign issue somewhere in the sensor chain for RM2, we would have expected the 'after' transfer function phases to differ between RM1 and RM2, so it's strange that they both have switched over to 180.

I've attached the transfer functions for RM1 and RM2 comparing the after vent measurements to the last measurements we had done for them with damping loops off, which was in 2022.

Non-image files attached to this report
LHO General (VE)
ryan.short@LIGO.ORG - posted 08:02, Thursday 22 May 2025 - last comment - 17:36, Thursday 22 May 2025(84532)
Ops Day Shift Start

TITLE: 05/22 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
OUTGOING OPERATOR: None
CURRENT ENVIRONMENT:
    SEI_ENV state: MAINTENANCE
    Wind: 11mph Gusts, 6mph 3min avg
    Primary useism: 0.03 μm/s
    Secondary useism: 0.09 μm/s
QUICK SUMMARY: HAM1 pumping continued overnight, but starting about 1.5 hours ago the pressure started rapidly climbing. No cause determined as of yet. VAC team has been contacted.

EDIT: Had the wrong channel trended, corrected in current attachment.

Images attached to this report
Comments related to this report
ryan.short@LIGO.ORG - 08:16, Thursday 22 May 2025 (84534)

The gate valve on top of HAM1 was closed and the pressure is now holding; trend attached.

Images attached to this comment
david.barker@LIGO.ORG - 09:23, Thursday 22 May 2025 (84537)

Note that we currently have a potentially confusing situation of two EPICS pressure channels for HAM1, only one of which is correct:

H1:VAC-LY_X0_PT100B_PRESS_TORR Is the correct channel, current value 1.3e-05

H0:VAC-LY_X0_PT100B_PRESS_TORR Is NOT the correct channel, unfortunately is misreports a better vacuum than we have, current value 1.5e-07

I went through all the vacuum MEDM screens and replaced the "H0" channels with the "H1" where ever I found them. Old MEDMs may still have the wrong value.

 

david.barker@LIGO.ORG - 10:43, Thursday 22 May 2025 (84540)

Vacuum FOM (nuc22) updated to new HAM1 gauge.

I've edited the caqtDM UI file for the Vacuum FOM to correct the HAM1 PT100B channel and remove the PT100A entry.

Images attached to this comment
janos.csizmazia@LIGO.ORG - 17:36, Thursday 22 May 2025 (84557)
Troubleshooted, see here: aLog no. 84556
Displaying reports 1001-1020 of 83128.Go to page Start 47 48 49 50 51 52 53 54 55 End