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Entry  Thu Jan 29 12:46:22 2026, Cece Ochoa, Update, , CE Cavity Design Update (4) 
Update for CE Cavity Arms + Modes https://docs.google.com/presentation/d/1-dXYylkAbNpHR4WVCx9Q8ryL_xGlH-JSSLXEUQg6b7Q/edit?usp=sharing
Entry  Tue Jun 3 11:54:06 2025, Cece Ochoa, Update, , CE Cavity Design Update CE_Arm_Cavity_.pdf
Update on the design for the CE Cavity Mirrors
Entry  Thu Nov 6 12:39:43 2025, Cece Ochoa, Update, ELOG, CE Cavity Design Update base_0_6_plot.pdfbase_0_7_plot.pdf
Updated mode placements and ROC. No thermal effects added yet.
Entry  Thu Nov 20 13:03:58 2025, Cece Ochoa, Update, ELOG, CE Cavity Design Update 11_20_update.pdf
Update on grouping 0+8th Order Modes
Entry  Thu Feb 12 12:53:51 2026, Cece Ochoa, Update, ELOG, CE Cavity Design Update 2_12_short_update.pdf
Update on HOM placement w/ cavity locking. Still verifying mode placement RoC: 28340m and 26874m
Entry  Thu Mar 12 13:18:49 2026, Cece Ochoa, Update, Interferometer Simulations, CE Cavity Design Update 
Animation showing how modes shift in the CE arm cavity for radius 27581m and mirror radius of40cm as the laser powers up the 1.5 MW. https://drive.google.com/file/d/1UNvWmONWYDzroelC5j_Z2emGSotyzcCC/view?usp=sharing
Entry  Thu Apr 23 11:32:48 2026, Cece Ochoa, Update, Interferometer Simulations, CE Cavity Design Update 
Update on CE Mirror RoC, simulation with FROSTI and cavity locking View Presentation
Entry  Fri Jul 5 14:12:32 2024, Liu, Update, Interferometer Simulations, CE BS Mechanical Resonances butterfly.pngdrumhead.png
The butterfly and drumhead mechanical modes for the aLIGO BS were calculated in COMSOL. The resonant frequencies for the two acoustic modes are 2.45 kHz and 3.61 kHz, matching the results in reference for instance.

For a quick projection for the resonant frequencies going from aLIGO to CE, the height and width of the BS are increased assuming the mass is increased from 14 kg to 70 kg, while keeping the aspect ratio fixed. The resonant frequencies for the two mechanical modes as a result becomes smaller, to 1.43 kHz and 2.11 kHz respectively, risking getting in the detection band.

Next step is to implement a mechanical ring with high stiffness outside the BS barrel to combat the decrement of the resonant frequencies of the relevant mechanical modes.

Entry  Tue Jun 3 11:50:08 2025, Pooyan, Update, CDS, CDS update 

There are three major issues with the lab's CDS system that should be addressed. They are ordered from the highest priority to the lowest.

  • CyMAC has stopped serving the fast channels (65k Hz)
    The channels are still there, and the data from the slow (16 Hz) channels is served correctly, but the fast data is not served. As a result, diagggui can not retrieve any information at the moment.
    Probably the issue is the same as the version conflict between daqd and nds2-server. After installing nds2-server on CyMAC and realizing that the conflict can not be resolved, I reverted the changes so that the CyMAC could be compatible with daqd, but there is a chance that there are still version conflicts that block the fast channels.
    I suspect that we have broken the MSC model when adding the new button. This could explain both the fasr-channels fault and the unexpected crashes.

    UPDATE 6/5
    Fixes this by rebuilding the models.
    Note for the future: The c1iop and c1msc models should be rebuilt together, even if no change has been made to c1iop.
  • The fast channels were not saved to the frames
    Reviewing the frame files showed that the daqd was only saving the 16 Hz data in the .gwf frame files. I had missed this because I only checked the existence and the integrity of the raw frame files, but never retrieved the high-frequency data itself to check it.
  • NDS2-server is installed, but does not distribute the data
    I managed to install the nds2-server and its satellite programs on the Chimay, and NFS mount the frame files on it. The server successfully chaches the channel names, frame files, and the data, but fails to list the channels for distribution.

Note: CyMAC machine was strangely disconnected from the network, and required manual reboot. I couldn't find any abnormal logs that could explain what happened.

Entry  Tue Jun 10 12:11:14 2025, Pooyan, Update, CDS, CDS update 
  • The MEDM models issue was fixed. The issue was that building the c1msc model alone was not enough and we had to re-build the c1iop as well, although no changes has been made to the c1iop. Added a note in the wiki on this for future reference.
  • For writing the fast channels to the frame files, our CDS system should have a GDS broadcaster. I followed this wiki page to set one, but it breaks the current daqd system. Asked about it earlier today on the CDS Mattermost channel and waiting for a response. 
  • Maybe I should continue the distributed scheme we have been trying for the nds2-server and let another machine on the network do this. 
  • Question: daqd has a feature to zero-out the bad data (NaNs), and it is currently on for our system. I don't think that it's a good idea to have this. Should I turn it off? 
Entry  Wed Jun 11 16:19:37 2025, Pooyan, Update, CDS, CDS update Screenshot_20250611_154834.pngf3k.pdf
  • Fast channels recorded to .gwf frame files
    • Had to add a DAQ Channels block to the c1msc model for those channel to be recorded in the .gwf frame files. The block is in the CDS_PARTS, and I just had to copy it to our model. Here is the example text for the channels:

      #DAQ Channels

      ONE_DAQ_CHANNEL 2048
      ANOTHER_DAQ_CHANNEL 1024
      SCIENCE_FRAME_CHAN* 1024
      UINT32_CHAN uint32 2048
      DAQ_CHANNEL_AT_DEFAULT_RATE

      I added two channels to the list (V0 and V1). Remember that the channel name should not be the full name, but just the part's name. In this case, I added these two channel names:

      V0_OUT
      V1_OUT

      with the default sample rate. 
  • The fast channels are recorded with an extra _DQ in their names. So, in ndscope and diaggui these two channels should be addressed as
    • C1:MSC-V0_OUT_DQ
    • C1:MSC-V1_OUT_DQ
  • Update 6/13: enabled recording of all the ADC voltage channels so that Tyler can use all the data for the noise floor calculation. attached is an example of diagggui with almost 30 hrs of data.
  • TODO: Enable daqd_wiper
Entry  Tue Feb 13 01:26:30 2024, Peter, Update, Interferometer Simulations, CARM Power Simulations Scenario_3_CARM.pdfScenario_3_CARM_Gouy.pdf
Cao's simulations of the circulating power and gouy phase through a single arm cavity of the interferometer have been reproduced. Images of the plots can be shown in the pdfs attached. There are approx. 400 lines in this code (scenario_3_carm) that produces these plots. This code also calls on a separate code source file (thermal_models) that defines many of the functions used in this main simulation. The thermal_models file consists of over 1000 lines. More work needs to be done to fully understand and document the scripts.
Entry  Wed Aug 9 17:35:26 2023, Shane, Update, CDS, Binary output chassis finished IMG_8685.jpegIMG_8686.jpeg
Finished the internal wiring for the binary output chassis today, which completes its assembly. Also secured ribbon cables and chassis lid with their respective screws. Note: one of the spade lugs' internal metal piece is a little loose and had to be reinserted after falling out once. Seemed secure after this, and I checked continuity on everything and it was all good.
Entry  Wed Aug 16 17:17:02 2023, Shane, Jon, Update, CDS, Binary input chassis powering correctly  IMG_9253.jpeg
Binary input chassis passed power-on test, and is lighting up as expected. Binary output chassis also successfully powered on. AA and AI chassis not powering on correctly, need to do some debugging to find the problem.
Entry  Tue Aug 8 17:03:22 2023, Shane, Jon, Update, CDS, Binary input chassis finished IMG_8681.jpeg
Finished assembly of the binary input chassis today, including DC on/off switch and LED installation. external cable assemblies still needed, but internal work done.
Entry  Thu Apr 16 14:04:46 2026, Mary, Update, Interferometer Simulations, Beam position optimization algorithm beam_position_optimization.pdf
 
Entry  Thu Jun 18 12:36:46 2026, Mary, Update, , Beam position optimization algorithm 
Slides
Entry  Thu Jun 25 11:42:29 2026, Mary, Update, TCS, Beam position optimization algorithm 

Weight Calibration: this study looks at how the thermal-compensation system should be tuned as the laser beam moves off-center on a detector mirror, with a fixed point-absorber defect in place. The optimizer that sets the actuator powers tries to flatten the wavefront, and it balances two kinds of distortion( i.e. surface distortion against substrate optical-path distortion) by a ratio that had been fixed at 20:1, but that value was only validated for a centered beam. So here I sweeps this ratio across beam positions from 0–5 cm along +x, with and without the absorber, re-optimizing the actuator powers at each position and judging each choice by the resulting power recycling gain from the fully locked interferometer.

Slides

Entry  Mon Mar 10 21:32:29 2025, Nathan, Physics, Electronics, Beam Profiling and PBS Measurements Beam_Profiling_2_20_(2).pdfbeamprfl.pngthumbnail_(6).jfif
Beam wasn't diverging, however maybe was about to diverge when measurements stopped? Will discuss the PBS measurements and how the voltage changed due to the wave plate.
Entry  Thu Apr 27 09:48:34 2023, Aiden, Summary, General, Batch 12 Bagging IMG_4279.jpgIMG_4278.jpg
I took batch 12 out of the oven and put them in a bag and placed the bag inside the clean room in the first large stainless steel container. I also looked at the small gauge that we felt like needed to be baked and I can confirm that without further cleaning around the inside of the gauge it should not be connected to the main vacuum. I have attached a photo of the inside of the gauge.
Entry  Tue Feb 11 08:07:02 2025, Luis, Update, VAC, Bake stopped  

[Luis, Ma]

Feb/10/25 4:00pm

Bake was stopped.

Entry  Fri Feb 16 18:37:28 2024, Jon, Update, VAC, Bake ended 6:23 pm 

I ended the bake of the UHV system (that began on Monday) at 6:23 pm today by switching OFF both PID controllers. The heaters elements were run at max power (24 V DC / 200 mA per element) during this bake, and I left them powered at the same level.

At the time, the instrument readings were as follows:

  • Left high-limit controller: 138 C
  • Right high-limit controller: 128 C
  • Left PID controller: 100 C
  • Right PID controller: 100 C
  • Main volume pressure: 8.17e-7 Torr
  • RGA volume pressure: 4.63e-7 Torr
Entry  Fri Feb 10 15:15:30 2023, Aiden, Update, General, Bagging First Batch 
Aiden Bagged and Tagged the first batch of stainless steel parts shown on the google spread sheet. 1. Removed two parts from the oven. 2. Place them in the ESD bag. 3. Seal bag with Kapton Tape. 4. Create label including part name and number underneath it. 5. Put label onto the side of the bag where it is not sealed with tape. 6. Placed bagged items into clean room on work table. ps. total bags in first batch = 4
Entry  Tue Feb 13 12:26:23 2024, Tyler, Update, Interferometer Simulations, BS Code Update thickness1.pdfbs_opd_homloss_h6cm_w2cm.pdf

I reproduced Cao's CE beamsplitter code (see below for example plots). I received the current info on the beamsplitter parameters for A+ and A# from GariLynn also. The next steps are to perform a similar power loss analysis on the anticipated A# beamsplitter.

Entry  Mon Jul 8 10:39:14 2024, Xuejun, Update, FLIR, Average Temperature Profile Average-Temperature-Profile.pdf

After taking data for each of the individual heater elements, I imported them into python and overlayed them to produce an average temperature profile. I rotated the 7 of the elements to align with element 1's profile and averaged them out. By setting the range to 28C - 33C (this gave the best visibility of the heating pattern) it gave the profile attached.

Entry  Thu Aug 3 18:03:42 2023, Shane, Jon, Update, CDS, Anti-Aliasing chassis complete IMG_8544.jpeg
We finished installing the internal power supply cables in the anti-aliasing chassis today, which concludes its assembly. Work on AI, BI, BO chassis still underway.
Entry  Thu Jul 13 15:31:21 2023, Jon, Update, General, Ant traps placed around lab 

In response to reports that ants have been observed in the lab, I placed five ant bait traps around the room today. Each is sitting on the floor on top of a piece of aluminum foil, in areas unlikely to be inadvertently stepped on. They contain liquid which will spill out if picked up, so please take care not to disturb them.

    Reply  Thu Jul 13 16:59:03 2023, Jon, Update, General, Ant traps placed around lab 

Update: After seeing the strong response to the first set, I redistributed them to the hottest spots and added one more trap.

Quote:

In response to reports that ants have been observed in the lab, I placed five ant bait traps around the room today. Each is sitting on the floor on top of a piece of aluminum foil, in areas unlikely to be inadvertently stepped on. They contain liquid which will spill out if picked up, so please take care not to disturb them.

 

Entry  Tue Jun 24 13:47:58 2025, Liu, Update, Interferometer Simulations, Alternative FROSTI A# optimization approach Update.pdf
Alternative FROSTI A# optimization approach
Entry  Tue Apr 4 16:43:53 2023, Jon, Update, VLC Electronics, Additional Thorlabs PDA10A2 PDA10A2.png
I ordered a second PDA10A2 and mounting post + spacer (which puts the aperture at the VLC's standard 3" beam height). These arrived today and I delivered them to the lab. They are sitting on the VLC table near the laser.
Entry  Wed Dec 14 18:34:33 2022, Jon, Configuration, Electronics, Adapter for 532 nm laser power supply laser_power.png
I installed an EU-to-US plug adapter for the 532nm laser's 9V power supply. I then re-measured the laser's power with the correct supply voltage (previously we had been using a 6V supply). At 9V, the max power is 0.83 W, so the laser is confirmed to be Class 2 as labeled.
Entry  Mon Jul 3 16:26:21 2023, Cao, Infrastructure, DAQ, Access and control Red Pitaya remotely and run it on local machine 
[Cao]

To access and control the Red Pitaya using Python locally on a machine within the local network, one should follow these steps:

  1. Start the SCPI server. This is achieved by first log onto the Red Piatay page

    rp-xxxxxx.local/ 
  2. Go to Development >> SCPI server and turn the server on. (Note : The server is currently running)
  3. Communication with Red Piataya is done through PyVista, install PyVista with:
     sudo pip3 install pyvisa pyvisa-py 
    This has been installed on Chimay. Ensure that you have pip3 install, if not, you can install it using:
     sudo apt-install python3 pip 
  4. To start talking to the RedPitaya, ensure you have the scipt
     redpitaya_scpi.py 
    in your local folder. This is the standard class that you will import to your code to establish connection with the Red Pitaya. This code can be found in directory
     ~/RedPiatya 
     or this link
    

Entry  Tue Jul 9 18:19:50 2024, Shane, Update, CDS, ADC-DAC loopback testing and IOLAN installation iolanServerTerminal.jpegADC-DAC_Loopback_Testing.xlsxupdatedc1msc.jpeg
[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.

    Reply  Tue Jul 16 18:43:07 2024, Shane, Update, CDS, ADC-DAC loopback testing and IOLAN installation Follow-up_ADC-DAC_Loopback_Testing.xlsx
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.

 

Entry  Mon Dec 4 21:27:53 2023, Shane, Update, CDS, ADC-DAC loopback test results adc-dac_loopback_testing_results.pdf
Here are the test results from today's ADC-DAC loopback tests. Channels 14 and 15 were the only ones behaving abnormally. Not sure what the issue is, but needs further debugging. The DAC output was as expected for both of them, but the corresponding ADC inputs were the same regardless of what offset was used (hovering around values of -4 and -5). NOTE: all measurements listed in the attached table are 'averages' in the sense that the ADC inputs and DAC outputs hovered around the listed values, changing by +1 or -1.
Entry  Thu Jul 27 14:46:55 2023, Shane, Jon, Update, Electronics, AA chassis DC on/off switch assembled 
Made the first DC on/off switch assembly today and installed in anti-aliasing chassis. Second switch assembly to be completed later.
Entry  Fri Oct 27 15:28:30 2023, Shane, Update, CDS, AA and AI chassis for CyMAC powered on and functional AI_chassis_lights_on.jpegAA_chassis_lights_on.jpeg
CyMAC updates: Switched out the faulty power regulator boards in the Anti-Aliasing and Anti-Imaging chassis. Both chassis are now powering up correctly with lights on and the correct voltages in/out of the power regulator board. Images attached. All chassis for the CyMAC now functional, so next step is mounting everything in the rack.
Entry  Thu Apr 9 12:40:24 2026, Xuesi Ma, Update, TCS, A# Ring Heater Design 

Slides discussing for A# Ring Heater design.

Entry  Tue May 13 12:41:06 2025, Tyler, Update, TCS, A# Profiles Update 
Slides on the A# ITM FROSTI profile modeling efforts can be found here.
    Reply  Wed Apr 1 15:02:30 2026, Tyler, Update, TCS, A# FROSTI Profiles Optimization 04/02/2026 

Slides discussing SURF, OPD, and SURF+OPD optimizations for idealized FROSTI A# profiles.

Quote:

Slides discussing updates on FROSTI A# profile optimizations. In particular, a new RMS function is defined which reduces inner-radii wavefront error variation to a greater degree.

Quote:

Slides covering a new approach to optimizing for A# FROSTI profiles. In particular, we start looking at just optimal RH correction. Once this profile is determined, we then minimize the residual further with FROSTI profiles.

Quote:

Slides updating progress on FROSTI A# irradiance profiles and reflector design. Edge roll-off is now included for thermoelastic deformation corrections.

Quote:

Quote:
Slides

 

A# Profile optimization update for 01/28/2026 group meeting.

Slides

 

 

 

 

    Reply  Thu Apr 16 13:14:42 2026, Tyler, Update, TCS, A# FROSTI Profiles Optimization 04/02/2026 

Slides discussing including overlapped irradiance profiles at the center of an A# ITM.

Quote:

Slides discussing SURF, OPD, and SURF+OPD optimizations for idealized FROSTI A# profiles.

Quote:

Slides discussing updates on FROSTI A# profile optimizations. In particular, a new RMS function is defined which reduces inner-radii wavefront error variation to a greater degree.

Quote:

Slides covering a new approach to optimizing for A# FROSTI profiles. In particular, we start looking at just optimal RH correction. Once this profile is determined, we then minimize the residual further with FROSTI profiles.

Quote:

Slides updating progress on FROSTI A# irradiance profiles and reflector design. Edge roll-off is now included for thermoelastic deformation corrections.

Quote:

Quote:
Slides

 

A# Profile optimization update for 01/28/2026 group meeting.

Slides

 

 

 

 

 

    Reply  Thu Mar 5 13:01:14 2026, Tyler, Update, TCS, A# FROSTI Profiles Optimization 

Slides discussing updates on FROSTI A# profile optimizations. In particular, a new RMS function is defined which reduces inner-radii wavefront error variation to a greater degree.

Quote:

Slides covering a new approach to optimizing for A# FROSTI profiles. In particular, we start looking at just optimal RH correction. Once this profile is determined, we then minimize the residual further with FROSTI profiles.

Quote:

Slides updating progress on FROSTI A# irradiance profiles and reflector design. Edge roll-off is now included for thermoelastic deformation corrections.

Quote:

Quote:
Slides

 

A# Profile optimization update for 01/28/2026 group meeting.

Slides

 

 

 

Entry  Thu Jan 15 12:52:58 2026, Tyler, Update, TCS, A# FROSTI Profiles 01/15/26 
Slides
    Reply  Wed Jan 28 11:29:30 2026, Tyler, Update, TCS, A# FROSTI Profiles 01/15/26 

Quote:
Slides

 

A# Profile optimization update for 01/28/2026 group meeting.

Slides
    Reply  Thu Feb 5 13:12:28 2026, Tyler, Update, TCS, A# FROSTI Profiles 01/15/26 

Slides updating progress on FROSTI A# irradiance profiles and reflector design. Edge roll-off is now included for thermoelastic deformation corrections.

Quote:

Quote:
Slides

 

A# Profile optimization update for 01/28/2026 group meeting.

Slides

 

    Reply  Thu Feb 19 12:59:47 2026, Tyler, Update, TCS, A# FROSTI Profiles 01/15/26 

Slides covering a new approach to optimizing for A# FROSTI profiles. In particular, we start looking at just optimal RH correction. Once this profile is determined, we then minimize the residual further with FROSTI profiles.

Quote:

Slides updating progress on FROSTI A# irradiance profiles and reflector design. Edge roll-off is now included for thermoelastic deformation corrections.

Quote:

Quote:
Slides

 

A# Profile optimization update for 01/28/2026 group meeting.

Slides

 

 

Entry  Tue Jul 1 12:39:42 2025, Tyler, Update, TCS, A# FROSTI Profile Optimization Update 
[Tyler, Liu]

Slides

Entry  Tue Aug 19 12:33:59 2025, Pooyan, Update, TCS, A# BS Update A#_beamsplitter_thermal_lensing.pdf
 
Entry  Tue Aug 15 16:10:06 2023, Celeste, Update, TCS, 8/15/2023 Simulation Progress Simulation_Progress__1_32nd_Model_(2).pdf
 
Entry  Fri Aug 11 10:57:20 2023, Celeste, Update, TCS, 8/11/23 Simulation Progress Simulation_Progress__1_32nd_Model_(1).pdf
 
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