ligo-ex ligo-ds
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ID Date Author Type Category Subject
  459   Wed Oct 16 13:58:59 2024 Luis MartinUpdateVACRGA Scan

The following figure displays data acquired on 10/09, and it shows that we are no longer below the cleanliness standard. Also, the system's pressure went up to 1.9x10-8 Torr (approximately 7x10-9 Torr previously). This might be due to a leak somewhere in the system. More tests will be performed later.

Attachment 1: 2024-10-09_PostBake1_ArO.png
2024-10-09_PostBake1_ArO.png
  458   Tue Oct 15 15:27:38 2024 Xuesi MaUpdateELOGTiming Chassis Update

I conducted separate tests on the '5015' and '3010a'. When powered individually, the '5015' outputs a signal at 33.55 MHz with an amplitude of 608 mV. It draws 1 A of current from the power source. The input signal for the '3010a' is 33.54 MHz with an amplitude of 670 mV (peak-to-peak) and a 15 mV DC offset. The output signal from channel 1 is a 65.5 kHz square wave with an amplitude of 3.28 V. The '3010a' draws 0.1 A of current.

Both the '5015' and '3010a' work fine when powered separately. However, when both are powered together, the power source behaves as if there is a short circuit. The current theory is that the switch or breaker is tripping, as it has a 1 A current rating. Since the combined current demand of both devices exceeds 1 A, this may be causing the issue.

Slides for 10/16/2024 Group Meeting

Attachment 1: 20241015_134152.mp4
Attachment 2: 20241015_133118.png
20241015_133118.png
Attachment 3: 20241015_133124.png
20241015_133124.png
Attachment 4: 20241015_133136.png
20241015_133136.png
Attachment 5: 20241015_133207.png
20241015_133207.png
Attachment 6: 20241015_133543.png
20241015_133543.png
Attachment 7: 20241015_133550.png
20241015_133550.png
Attachment 8: 20241015_133555.png
20241015_133555.png
Attachment 9: 20241015_133300.png
20241015_133300.png
Attachment 10: 20241015_133643.png
20241015_133643.png
Attachment 11: 20241015_134202.png
20241015_134202.png
Attachment 12: 20241015_135353.png
20241015_135353.png
  457   Wed Oct 9 13:52:31 2024 TylerUpdateTCSRIN Update 10/09/2024

I tried adjusting the gain settings on the photodetectors to check if this would help improve the RIN spectra measurements. Overall, it doesn't look like it does, and if anything, looks worse. I assume this is so because as the gain is lowered, the amount of detectable signal from the FROSTI becomes smaller and smaller.

Attachment 1: RIN_plots_CH0.pdf
RIN_plots_CH0.pdf
  456   Thu Oct 3 19:35:04 2024 ShaneUpdateCleanroomCleanroom cleaning and particle count
[Luke, Michael, Cynthia, Mary]

cleaning cleanroom and particle count

  • 12:25 pm: started particle count
    • zone 3:
      • 0.3 u: 4614
      • 0.5 u: 872
      • 1.0 u:83
    • zone 4:
      • 0.3 u: 2411
      • 0.5 u: 415
      • 1.0 u: 83
  • 12:48 pm: began surface check and wipedown, including softwalls
  • 1:20 pm: started vacuuming the floor
  • 1:30 pm: finished vacuuming the floor
  • 1:34 pm: started mopping the floor
  • 1:40 pm: finished mopping the floor
  • 1:40 pm: started cleaning the buckets
  • 1:42 pm: started mopping with IPA wipes
  • 1:50 pm: finished mopping with IPA wipes
  • 1:51 pm: changed sticky floor mats
  • 3:44 pm: started particle count
    • zone 3:
      • 0.3 u: 3207
      • 0.5 u: 624
      • 1.0 u: 83
    • zone 4:
      • 0.3 u: 916
      • 0.5 u: 83
      • 1.0 u: 0
  455   Wed Oct 2 14:49:59 2024 LiuUpdate FROSTI ETM actuation
Proposed FROSTI ETM actuation on the HOM7 resonance. Animation
  454   Wed Oct 2 13:38:00 2024 CynthiaUpdateInterferometer Simulationscavity scan with averaged O4 ETM coating as plume
Attachment 1: O5plumevsCoating.png
O5plumevsCoating.png
Attachment 2: O5CoatAvgpt5.png
O5CoatAvgpt5.png
Attachment 3: O5AVgcoatingFROSTIpt5.PNG
O5AVgcoatingFROSTIpt5.PNG
  453   Wed Oct 2 12:20:43 2024 TylerUpdateTCSUpdated FROSTI Analysis 10/02/2024
Attached below are updates on current FROSTI prototype analysis.
Attachment 1: FROSTI_Analysis_Updates.pdf
FROSTI_Analysis_Updates.pdf
  452   Wed Oct 2 12:05:42 2024 Luke Update Ringheater modeling Update

Power point slides

  451   Wed Oct 2 10:31:46 2024 Xuesi MaConfiguration Group Meeting Slides 10/2/2024

Group Meeting slides for Non-deterministic Heater Response.

Attachment 1: Group_Meeting_10_2.pdf
Group_Meeting_10_2.pdf
  Draft   Tue Oct 1 19:41:23 2024 ShaneUpdateCDSCyMAC Timing Chassis Issue
[Shane, Luis] Summary of the issue we've been having with the timing chassis: when we connect only the Valon 5015 to power, the timing signal comes out of it sinusoidal as expected and the status lights are steady and all looks good. As soon as we connect the 3010 to power, the signal (both coming out of the 5015 and coming out of the 3010) go flat and the status lights of the 5015 start to flicker. We think what may be going on is that the 5015 is drawing just enough power to survive on its own, but when the current gets split to go to the 3010 as well, the 5015 takes more than it needs and becomes overpowered, and thus no longer outputs anything. We want to test further by powering them with two separate power supplies, but we need another one of the power connectors for the 3010 (the only one we have branches out from the connector to the 5015 and we don't want to cut any of the wires). Images of the inside of the chassis, along with two roughly sketched circuit diagrams (one showing the current setup, in which they're powered by the same source, and one showing a possible test set up, in which they're powered separately.
Attachment 1: IMG_5917.jpeg
IMG_5917.jpeg
Attachment 2: IMG_5803.jpeg
IMG_5803.jpeg
Attachment 3: IMG_5804.jpeg
IMG_5804.jpeg
  448   Wed Sep 25 09:06:09 2024 Luis MartinUpdateVACRGA Scans
RGA Scan Comparison

The following images compare the RGA scans from 9/23/24, after the first bake with the new vacuum system, with those from 3/14/24, after bake 12 with the old system.

The first image shows a graph of the raw data and includes the calibrated leak for both curves. As we can see, our new system meets LIGO standards of cleanliness.

The second graph contains the plot of the normalized data.

Attachment 1: 24overlay.png
24overlay.png
Attachment 2: 24overlayNormalized.png
24overlayNormalized.png
  447   Mon Sep 23 15:11:21 2024 TylerUpdateScripts/ProgramsEffective Emissivity Analysis and RIN Update

A quick update on the effective emissivity analysis for the CIT FROSTI testing:

I was able to (roughly) match the OPD data to a referenced COMSOL model, with an applied power of 12.6 W (as seen below). However, when changing the emissivity of the ETM in COMSOL, the dT profiles do not seem to change much. I am not sure as to why this is the case at the moment, and will continue to look further.

Additionally attached are the current RIN measurements of the FROSTI prototype. Shown is the PSDs of both channels, in reference to their individual backgrounds.

Attachment 1: OPD_Plot.png
OPD_Plot.png
Attachment 2: Temp_emiss_plot.png
Temp_emiss_plot.png
Attachment 3: rin_photodectors.png
rin_photodectors.png
Attachment 4: RIN_setup.jpg
RIN_setup.jpg
  446   Mon Sep 23 15:00:41 2024 Cynthia UpdateInterferometer Simulationscorrections on assumption for O5 coating
The document recording ETM07 and ETM08 coating (T2300093) was discussed: the current plume files are not necessarily correct in a way that LIGO lab have tried to add it on uncoated ETM such as ETM07 and it does not match what the coated ETM07 would look like. the plume should be added on top of the uncoated ETM instead of assuming an ideal ETM. According to Garilynn, the imperfection on uncoated ETM matters. So far the possible ETM data used for O5, ETM 11,14,19, and 20 are all uncoated, and different ways could be used to predict the plume, including the plume data on LIGO dcc or subtract the uncoated data from the coated for O4 ETM and use that as another guessed plume.
Attachment 1: Uncoated_S1_ETM07-v2.pdf
Uncoated_S1_ETM07-v2.pdf
  444   Mon Sep 23 08:29:49 2024 LukeUpdateInterferometer SimulationsRingheater update

Ringheater Update

If the link does not work here is the file.

Attachment 1: 20240923_Update.pptx
  443   Mon Sep 16 15:18:59 2024 Cynthia UpdateInterferometer Simulationsa breakdown of FROSTI and thermal effects and the resulting cavity scan
Attachment 1: ligo_update_9_16_(1).pdf
ligo_update_9_16_(1).pdf
  442   Mon Sep 16 14:59:51 2024 TylerUpdateTCSFLIR RIN Update 09/16

Below is the dark noise spectrum of the Red Pitaya, which was measured over the course of a weekend. Additionally, I have successfully measured a signal from the photodetectors with the FROSTI as the IR source, so it seems there shouldn't be any worry of these particular detectors not being feasible for the RIN measurement.

Attachment 1: adc_noise_floor_photodectors.png
adc_noise_floor_photodectors.png
  440   Mon Sep 16 13:51:23 2024 Luis MartinUpdateVACRGA Scans

[Luis, Luke}

Three RGA scans were taken. The improvement in the amount of HC in the vacuum is visible across the different measurements. Images are attached.

Attachment 1: 2024-09-11_PostBake1_ArO.png
2024-09-11_PostBake1_ArO.png
Attachment 2: 2024-09-13_PostBake1_ArO.png
2024-09-13_PostBake1_ArO.png
Attachment 3: 2024-09-16_PostBake1_ArO.png
2024-09-16_PostBake1_ArO.png
  439   Mon Sep 16 07:28:16 2024 LukeUpdateInterferometer SimulationsRing heater update
Attachment 1: 20240916_Ringheater_updates.pptx
  438   Mon Sep 9 21:02:37 2024 LukeUpdateVACSteadystate temperature of flanges

I measured the temperature of the flanges and reconnected the RGA turning on its filament. I then turned off the PID controllers.

Here is a table that has the temperature of the different parts of the vacuum chamber.

Electronics Temperature (C)
Pressure gauge (Main volume) 81
Main turbo pump 67
RGA 53
Pressure gauge (RGA volume) 60
Cal leak 48
Mini tubo pump 46
Pirani gauge (1.33") 46
conical nipple (2.75") 82
Lid 112
Barrel lower 125
Barrel upper 122
RGA volume 125
Bottom of chamber 117
  437   Mon Sep 9 14:27:36 2024 PooyanInfrastructureComputersChimay backup attempt

One ongoing work is to make all lab machines automatically backed-up on Scribe on a daily basis. The updates should be boatable and stored for some time (potentially a few weeks) on Scribe. Making whole disk images has already been tried for some of the machines with no problems. (e.g., Cymac and WorkStations)

The same thing can not be done with Chimay though, as it currently has one huge RAID-controlled volume that stores all the information (OS, home directories, and NDS-downloaded data). Creating daily full disk images of such a system is not practical. 

Here is the plan we came up with to overcome this issue:

  1. Create one full disk image of Chimay and store it on Scribe (it was already done)
  2. Move the nds-downloaded raw data temporarily to Scribe and remove it from Chimay
  3. Make another full disk image of Chimay
  4. Burn this image to a single disk and boot chimay with it
  5. Restore the rest of Chimay disks and move the NDS data back

     

On the weekend (Sat and Sun 9/7-8) I tried to execute these steps. There wasn't enough free space left on Scribe to move all the NDS data to it, so I stored part of this data temporarily on WS4. Then I also checked storage-consuming directories and, in one case, removed some non-important stored files. As there was no free space left on Scribe to execute step no. 3, I initiated storing the image on WS3. Unfortunately, a couple of different trials of the image-creation process failed as there was not enough free space on WS3 to accommodate Chiamy image as well. I was not able to reduce the image size such that it can be stored on WS3. 

 

These are the options left for us to get this work done. 

  1. Distribute the NDS files between different machines to make enough free space on Scribe for the image and then follow the previous plan
  2. Shrink the Chimay drive size, create the image and then follow the previous plan
  3. Temporarily transfer some services to Megatrone (Network gateway, Wiki, elog) and recreate chimay and its services from scratch
  436   Mon Sep 9 12:36:45 2024 MichaelUpdateInterferometer SimulationsUpdate on Analysis of Mode Mismatch Minimization in A#
I have taken a closer look at the solution curve in the mirror parameter space which I have searched, focusing on the "resilience" of specific points, with the plan to analyze how certain conditions of the interferometer change as we move along this solution curve.
Attachment 1: SRC_Mode_Mismatch_Update_9_9_24.pdf
SRC_Mode_Mismatch_Update_9_9_24.pdf
  435   Fri Sep 6 14:34:52 2024 Luke UpdateVACHeating tape work

On the 5th I had tried to start baking the vacuum chamber however certain parts of the chamber were getting too hot and causing the controllers to shut off. So I turned them off so that the next day I could rearrange the temperature probes. I then on the 6th set them up so that instead of overshooting the temperature they would be a little low in places.

After being left over night the cooler parts of the vacuum chamber got much closer to the desired temperature of 120C.

Here is a table of the temperatures of the sections of the chamber. Note: After these measurements were taken the PID controllers were set to 125C.

Location   Temperature (C)
Lid (PID controller 1 emergency shutoff) 108
Barrel lower (PID controller 1) 120 
Barrel upper (PID controller 2 emergency shutoff) 118
RGA volume (PID controller 2) 120

Here is a table of temperature of the flanges that have electronics.

Electronics Temperature (C)
Pressure gauge (Main volume) 79
Main turbo pump 64
RGA 51
Pressure gauge (RGA volume) 55
Cal leak 47
Mini turbo pump 50
Pirani gauge 45 

Other temperatures of note:

The optical table was about 38C

The cleanroom was around 33C (~91F)

  434   Tue Sep 3 18:24:17 2024 TylerUpdateCDSCymac Timing Chassis Issue
[Tyler, Jon]

The timing chassis used for the cymac has been shut off due to an unknown issue causing its supplied current to fluctuate. All real-time models will be suspended until a solution is found.

  433   Tue Sep 3 15:52:56 2024 LukeUpdateVACHeater tape initilization

[Luke, Tyler, Jon]

On the 3rd we set up the pid controllers for the heater tapes and after putting on the insulation we started heating them up. We first brought it to ~50C and let it stabilize, there was about a 6-7 degree difference between the RGA and the barrel temperature, with the barrel being higher. We then brought it to 60 then 70C it still maintained the slight difference between the RGA and barrel temperatures.

Here is a table of the temperatures of the flanges connected to electronics as I left it.

Electronics Temperature (C)
Pressure gauge (Main volume) 58
Main turbo pump 45
RGA 37
Pressure gauge (RGA volume) 39
Cal leak 40
Mini tubo pump 36
Pirani gauge 37

Notes: I removed the electronics from the pressure gauge (main volume) because while it was below the required threshold it was still quite high compared to the other flanges.

  432   Sun Sep 1 16:17:40 2024 LukeUpdateVACVacuum chamber leak checking and re-applying heating tape

[Luke, Luis, Cinthia, Michal, Tyler]

On the 26th Cinthia, Michal, and I took off the insolation on the vacuum chamber and re-routed it to include the new RGA volume. 

The next day Luis and I finished up the last of the flanges to be attached. We attached the Pirani gauge with a conical reducing nipple to the 2.75" port on the vacuum chamber. We then preformed the Helium leak testing, both flanges were quite low the 2.75" flange had a leak of 1.68e-10 torr and the 1.33" flange of 5.5e-12 torr. The leak on the 1.33" flange was so low it was difficult to know how much of it was real and how much was just noise.

  431   Thu Aug 29 16:39:34 2024 LukeUpdateVACPhotos of heater tape
Attachment 1: IMG_2052.jpeg
IMG_2052.jpeg
Attachment 2: IMG_2051.jpeg
IMG_2051.jpeg
Attachment 3: IMG_2048.jpeg
IMG_2048.jpeg
Attachment 4: IMG_2047.jpeg
IMG_2047.jpeg
Attachment 5: IMG_2046.jpeg
IMG_2046.jpeg
Attachment 6: IMG_2044.jpeg
IMG_2044.jpeg
  430   Tue Aug 27 18:37:40 2024 LukeUpdateInterferometer SimulationsRingheater model update
Updated the model to produce a more circular deformation in the HR surface. The first three attachments are from irradiance patterns gotten from ray tracing. The last is from a pre-defined irradiance pattern.
Attachment 1: Initial_1W.png
Initial_1W.png
Attachment 2: Increased_rays_100W.png
Increased_rays_100W.png
Attachment 3: Increased_rays_more_100W.png
Increased_rays_more_100W.png
Attachment 4: Initial_100W.png
Initial_100W.png
  429   Tue Aug 27 15:01:26 2024 LukeUpdateVACRGA line leak testing

[Luke, Tyler]

On the 27th Tyler and I ran the RGA leak test again with the electron multiplier on. These were the leaks we measured. The chamber's overall pressure was at ~6e-8 torr. 

Connection Leak rate (torr)
Tee - RGA 3.92e-11 (very low)
Tee - Cal leak 4.77e-11 (very low)
Tee - ZLR (2.75"-4.5") 4.97e-11 (very low)
ZLR (2.75"-4.5") - Reducing Cross 2.45e-9   (low)
Cross - Elbow 7.36e-11 (very low)
Elbow - Pressure sensor 2.36e-11 (very low)
Cross - Turbo pump (small) 8.07e-9   (lowish)
Cross - Gate valve 4.02e-11 (very low)
Gate valve - Port 2.27e-9   (low)
Port - ZLR (6.0"-8") 1.11e-9   (low)
ZLR (6.0"-8") - Turbo pump (large) 1.00e-10 (very low)
Port - Pressure sensor 1.05e-10 (very low)
Port - Up to air valve 1.08e-11 (very low)
Port - Blank 5.58e-10 (very low)
Port - Feed though port 1.21e-11 (very low)
Lid 1.11e-11 (very low)

 

 

  428   Mon Aug 26 14:42:04 2024 Cynthia UpdateInterferometer Simulationscurrent status on cavity scan with effects of FROSTI
I used the code and arm cavity model used for previous O5 study on mirrors and HOM (the pdf of the study and the result can be found at https://dcc.ligo.org/LIGO-G2100878), but it seems like the result I obtained is different from the study result. Since my cavity scans codes have a large portion of it relying on this code, I will have to go over the study result and the code to make sure there is no issue with that code itself first. There are also some other updates or issued encountered when I tried to plot the mirror maps with effects of FROSTI.
Attachment 1: LIGO_updates_8_26.pdf
LIGO_updates_8_26.pdf
  427   Fri Aug 23 16:08:32 2024 LukeUpdateVACRGA line leak testing

[Luke, Luis, Jon, Tyler]

On the 22nd Dr. Richardson showed Luis, Tyler and I how to preform a leak test with the RGA. We did the initiall test and found a few leaks two were particuarly bad highlighted in orenge below. To try and remidy this we planned on replacing the copper gaskests on the leaking flanges. We then began taking the two problem flanges off, but seven of the eight bolts holding on the turbo pump were over tightened and had seized. So after we got them off we postponed the rest of the work to the next day.

On the 23nd Luis and I reattached the badly leaking flanges with new copper gaskets. We then preformed the Helium leak test with the RGA. As seen in the table below we weren't able to majorly changed the leaks in the two flanges.

 

Connection Initial  After disassembly
Tee - RGA 3.1e-9 -> 2.4e-9 9.2e-9
Tee - Cal leak Low Low
Tee - ZLR (2.75"-4.5") Low 9.2e-9
ZLR (2.75"-4.5") - Reducing Cross 2.1e-8 -> 1.9e-8 3.6e-8 -> 9.3e-9
Cross - Elbow Low 1.2e-9
Elbow - Pressure sensor Low 2.9e-9
Cross - Turbo pump (small) 2.1e-8 -> 3.1e-8 6.9e-8 -> 2.2e-8
Cross - Gate valve Low Low
Gate valve - Port 2.4e-9 -> 2.2e-9 1.2e-9
Port - ZLR (6.0"-8") 1.1e-9 N/A
ZLR (6.0"-8") - Turbo pump (large) Low N/A
Port - Pressure sensor Low N/A
Port - Up to air valve Low N/A
Port - Blank Low N/A
Port - Feed though  port Low N/A
Lid Low N/A

 

  426   Mon Aug 19 07:11:55 2024 CynthiaUpdateInterferometer Simulationscavity scans with FROSTI effects
Attachment 1: LIGO_update_8_19.pdf
LIGO_update_8_19.pdf
  425   Fri Aug 16 12:51:46 2024 Luis MartinUpdateVACUpdate on vacuum chamber status

[Luis, Luke, Tyler]

Vacuum chamber parts were finally received and assembled. After whipping down the parts, the blank was removed from the reducing cross. Then, the zero-length reducer was attached. Lastly, we installed the T that had the argon leak and RGA. The final pump down showed signs of an improved seal since the pressure dropped quite fast. This pressure is well bellow the limit required to use the RGA, argon test leak could be performed some time next week.

Attachment 1: IMG_1910.HEIC
Attachment 2: IMG_1911.HEIC
Attachment 3: IMG_1909.HEIC
Attachment 4: IMG_1912.HEIC
  424   Mon Aug 12 17:09:04 2024 Cynthia UpdateInterferometer SimulationsO4 vs O5 cavity scans with ITM plume guess or ETM
So far the proposed solution for what to use for O5 ITM mirror for SIS simulations is either the plume guess file or using the O5 ETM mirror for ITM. I had ran a cavity scan for both of these possibilities and it seems like the results produced are fairly different. The next step is most likely moving on to adding the Frosti effects including both of the proposed possibilities, and before this, a few confirmations and verifications are needed using similar previous studies to make sure my code produce the right result.
Attachment 1: O5_plots_and_tables.pdf
O5_plots_and_tables.pdf
Attachment 2: O4_plots_and_tables.pdf
O4_plots_and_tables.pdf
Attachment 3: ETM12mapO5.png
ETM12mapO5.png
Attachment 4: Screenshot_2024-08-12_at_5.05.31_PM.png
Screenshot_2024-08-12_at_5.05.31_PM.png
  423   Mon Aug 12 16:35:30 2024 Luke Update Ringheater modeling Update
Attachment 1: HR_surface_deformation.png
HR_surface_deformation.png
Attachment 2: Irradiation_pattern_input.png
Irradiation_pattern_input.png
Attachment 3: HR_surface_deformation_other.png
HR_surface_deformation_other.png
  422   Mon Aug 12 16:24:34 2024 TylerUpdateCleanroomRIN Measurement Update 1
[Tyler]

For some preliminary tests, I moved the IR photodetectors outside of the cleanroom and onto the other optical table. The basic goal was to obtain a signal from both photodetectors. To achieve this, one of the heater cartridges used for early FLIR measurements months ago was hooked up to a power supply (PS). The PS was set to supply 0.20 A with a voltage of 2.8 V; the corresponding power is thus 0.56 W. With this, I was able to measure a signal using the Red Pitaya, the device that will be used for following RIN measurements.

Quote:
[Tyler]

I have begun moving parts into the cleanroom for the upcoming FROSTI RIN tests that will be conducted within the next few weeks. While waiting for the rest of the equipment to arrive to perform the full-scale tests, I have additionally moved the FROSTI under the shelf above the optical table, where it will stay for the meantime. As always, please use caution when in the cleanroom. Aside from the FROSTI, the IR photodetectors that will be used for the test are delicate and costly to replace.

 

Attachment 1: Basic_setup.jpg
Basic_setup.jpg
Attachment 2: RP.jpg
RP.jpg
  421   Tue Aug 6 13:07:07 2024 XuejunUpdateInterferometer Simulations 
[Xuejun]

The width and location of the measured in-air change in temperature profile has been determined to be 0.045m and 0.137m respectively. Subsequently, a fake irradiance profile was able to be generated that best resembled what the actual irradiance profile could be using this information for testing in COMSOL. The generated irradiance profile that output the most similar change in temperature profile as the measured in-air profile has been included as well as the change in temperature profile it produced on the blackbody screen "test mass" model in COMSOL.

Attachment 1: Thermal_model_image.png
Thermal_model_image.png
Attachment 2: generated_irradiance_profile.png
generated_irradiance_profile.png
  Draft   Sun Aug 4 09:01:01 2024 MichaelUpdateInterferometer SimulationsUpdate on SRC Mode Mismatch Analysis
An update on my analysis to minimize mode mismatch/scattering by introducing toroidal mirrors to the SRC.
Attachment 1: SRC_Mode_Mismatch_Update_8_2_24.pdf
SRC_Mode_Mismatch_Update_8_2_24.pdf
Attachment 2: SRC_Mode_Mismatch_Update_8-12-24.pdf
SRC_Mode_Mismatch_Update_8-12-24.pdf
  419   Fri Aug 2 13:50:22 2024 ShaneUpdateCDSSerial Comm. Test (Agilent Turbo Pump)
Did a brief communication test with the agilent turbo pump today, to see if we could get serial communications up and running for it. Used a simplified python script with sockets package to establish a connection and send a simple command to query the pump's operational status. The connection was successful, and had no issues establishing. The command also sent successfully, and received a response. The response didn't make sense, though, as all the possible statuses correspond to integers 0-7, and this test returned the integer 15. Need to troubleshoot some more to figure out why it's returning nonsense values. Possible match-up issue with the way the information is being encoded on each end? At the very least, connection and command sending are both working fine, and this showed that the pin-out connections we were assuming (image attached) are correct for basic connection to work.
Attachment 1: pinouts.jpeg
pinouts.jpeg
  418   Tue Jul 30 07:42:47 2024 JonInfrastructureGeneralCable tray installed in 1119
Yesterday I installed another 5' cable tray in 1119, for permanently routing Ethernet lines to the L-bench. It is securely bolted to the top of the electronics rack, on one end, and to the top of the glass-door storage cabinet, on the other. This eliminates the need for the cable ramp which previously sat behind the rack.
Attachment 1: cable_tray_1119.jpg
cable_tray_1119.jpg
  417   Mon Jul 29 14:30:16 2024 TylerUpdateCleanroomRIN Measurement Set-up
[Tyler]

I have begun moving parts into the cleanroom for the upcoming FROSTI RIN tests that will be conducted within the next few weeks. While waiting for the rest of the equipment to arrive to perform the full-scale tests, I have additionally moved the FROSTI under the shelf above the optical table, where it will stay for the meantime. As always, please use caution when in the cleanroom. Aside from the FROSTI, the IR photodetectors that will be used for the test are delicate and costly to replace.

Attachment 1: RIN_FROSTI.jpg
RIN_FROSTI.jpg
  416   Mon Jul 29 13:39:16 2024 TylerUpdateDAQRTD Parameter Calibration
[Tyler]

Using the data taken during the FROSTI testing at Caltech, I attempted to find a better calibration of the RTD sensors, given our past issues with inaccurate readings. The fit parameters, alpha and beta, are still all different from the initial values given to us by Fralock (alpha = .003, beta = 1.003e-6, R_0 was not given), but the true values will differ based on factors such as part geometry.

Quote:
Refitted RTD calibration, neglecting quadratic term:

       R_0 (ohm)   Alpha (1/C)

RTD 0   79.3962   0.002031

RTD 1   78.2874   0.002530

RTD 2   80.9775   0.002381

RTD 3   74.2947   0.003684

RTD 4   80.3199   0.002157

RTD 5   78.2106   0.002297

RTD 6   76.6825   0.002438

RTD 7   82.6645   0.002458


Measurements taken can be found here. An uncertainty of 1 C was assumed for temperature.

Quote:
[Jon,Tyler]

We noticed that the RTD temperature readings given on the Cymac were off, and traced the issue to miscalibration in the relationship between the resistance and temperature of each RTD (Callendar-Van Dusen eqn). Below is the table of values inferred from independent measurements of temperature and resistance to rectify this problem. This data was then fitted to better determine the coefficients present in the temperature-resistance relation:

       R_0 (ohm)   Alpha    Beta

RTD 0   80.8674   0.001315   4.273e-6

RTD 1   79.5704   0.001887   3.7873e-6

RTD 2   81.7334   0.002014   2.1724e-6

RTD 3   74.3060   0.003677   3.6022e-8

RTD 4   81.1350   0.001761   2.3598e-6

RTD 5   77.9610   0.002423   -7.5192e-7

RTD 6   78.7980   0.001373   6.2909e-6

RTD 7   83.8616   0.001890   3.3529e-6

 

 

Attachment 1: RTD_Recal_params.png
RTD_Recal_params.png
Attachment 2: RTD_recal_plots_fin.png
RTD_recal_plots_fin.png
  415   Mon Jul 29 12:23:10 2024 LiuUpdateInterferometer SimulationsUpdate on mechanical resonances of CE BS with stiffener ring
Update on mechanical resonances of CE BS with stiffener ring is attached.
Attachment 1: eigen_freqs_merged.pdf
eigen_freqs_merged.pdf
  414   Mon Jul 29 12:20:56 2024 LiuUpdateInterferometer SimulationsUpdate on wavefront actuation with astigmatically driven RH for CE
Update on wavefront actuation with astigmatically driven RH for CE is attached.
Attachment 1: SURF_nonastig_merged.pdf
SURF_nonastig_merged.pdf
  413   Mon Jul 29 12:18:52 2024 LiuUpdateInterferometer SimulationsUpdate on FROSTI O5 ETM profile optimization
Update on FROSTI O5 ETM profile optimization is attached.
Attachment 1: pdf_merged.pdf
pdf_merged.pdf
  412   Fri Jul 26 17:25:42 2024 JonInfrastructureComputersNew workstation ws4 installed in 1129

Today I installed the second desktop workstation in 1129. The new machine is an Intel NUC13ANHi5, with a 12-Core Intel i5-1340P CPU, 32GB DDR4 RAM, and a 1TB SSD.

I loaded it with a fresh installation of Debian 12 and installed the LIGO CDS workstation (control room) tools. It is assigned the hostname ws4 and and the static IP address 192.168.1.19 on the local lab network. Like the other CDS workstations, there is just one user account accessible with the usual credentials.

The machine is fully set up and ready for use.

Attachment 1: ws4.jpg
ws4.jpg
  411   Mon Jul 22 18:19:34 2024 LukeUpdateVACZero length reducer stuck bolts

Today, I borrowed a bolt extractor drill bit from the machine shop to remove some stuck bolts from the zlr. Before starting, I laid down a sheet of aluminum foil on the work table and wiped down all the tools I was going to use. I began by drilling a small pilot hole and then enlarged it with a 5/32 drill bit. However, when I attempted to use the bolt extractor, it didn't grip the bolt effectively. Our bolts were too seized, causing the extractor bit to repeatedly slip instead of gaining traction.

Attachment 1: image_2024-07-22_181607501.png
image_2024-07-22_181607501.png
Attachment 2: image_2024-07-22_181632965.png
image_2024-07-22_181632965.png
  410   Tue Jul 16 18:43:07 2024 ShaneUpdateCDSADC-DAC loopback testing and IOLAN installation
UPDATE: Follow up ADC-DAC loopback testing now complete, matching all the ADC channels to a single DAC channel, and then matching all the DAC channels to a single ADC channel (see attached xlsx file or access directly here). Also note c1msc model file has been updated to include the second set of 16 ADC channels. The newly added channels also have their own filter modules, but those are not needed for anything other than the loop-back testing and can now be deleted if we don't want to keep them.

Quote:
[Shane, Jon]

Finished ADC-DAC loopback testing today (see attached xlsx file or access directly here). All looks well with the first 8 channels, with the gain hovering just under 2. Also edited c1msc model in simulink to add channels 7-15 (the last 8 channels), and changed the rate back to 64K. See image 1 for the updated c1msc model. The last 8 channels are also looking good and show no problems, with slightly more scattering for the gain, but all values very close to 2.

We also installed the new eight-channel Perle IOLAN SDS8 terminal server today. Image attached.

NOTE: When we were installing it, we noticed an energized wire dangling from the 24V power supply. Has since been fixed and put back into place.

 

Attachment 1: Follow-up_ADC-DAC_Loopback_Testing.xlsx
  409   Mon Jul 15 15:52:40 2024 MichaelUpdateInterferometer SimulationsaLIGO locking with varying SRC mirrors and measuring mode mismatch
Attachment 1: SRC_Astigmatism_Analysis_7_15_24.pdf
SRC_Astigmatism_Analysis_7_15_24.pdf
  408   Mon Jul 15 15:44:52 2024 Cynthia UpdateInterferometer Simulationsperformed cavity scans with thermal effects and ring heater
Attachment 1: cavity_scan_07_15.pdf
cavity_scan_07_15.pdf
  407   Mon Jul 15 14:49:06 2024 PooyanUpdateComputersSynology NAS server setup

Installed a Synology NAS server (Synology RackStation RS1221) in lab room 1129, with host name “scribe” and ip “192.168.1.17”. It is mounted on the rack and each of its 8 storage bays has a 2TB SSD disk. It will be used to set up automated backups of all the lab machines (e.g., chimay, logrus, megatron).

One shared storage is set on it with SHR-2 as its RAID type. It can tolerate the failure of two disks and has 10.4TB of total capacity. 

We can use both rsync and dd to create backups of the system. A suggested backup schedule could be daily rsync backups and bi-weekly disk snapshots using dd. 

 

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