[Tyler, Shane, Mohak, Cynthia, Luke, Michael, Luis]

The tabletops have been attached to the workbench frames. Unfortunately, one of the tabletops came out of the box with a large scratch and small dent in the middle. One of the electric top shelves is ready to be attached to the undamaged table, but the other is yet to be opened. Assembly will be completed Wednesday morning.

• 01:50 pm: Starting test position 34 mm distance to black wall.
• Parameters : 0.100 A, 1.5 V and the temperature inside the mirrors 40°C.
• 2:09 pm : Finished the test and figured out this position it is too far the black wall so now we change for more close position.

• 2:17 pm: Starting test in another position: 10 mm distance to the black wall( this measurement is between the black wall and the aluminum lid)
• 2:26 pm : Finished this second tried and take a snap. The image is attached below.
• The name for the picture for this tried is “AcquisitionImage(Apr-21-2023_14 26)”.

Note: The second tried the temperature didn't up more than 40°C for 8 minutes so I change the current for a few seconds. I started with 0.98 A with 1.7 V and up until 0.350 A with 2.5 V, just for a few seconds and in this way the temperature up to 72°C and I get the snap.
The next step should be understand the problem with the shape and work in changes for get the triangle in the FLIR image.

FLIR: After some adjustments, the plot generated from the FLIR measurements look much more symmetric (see attachment). There are more included grid points, which smooths out the curve as compared to last week.

Red Pitaya: It looks like a new OS update was released for the RP, which includes a new Python API (was previously only available in C). I'm going to try and update the one we have currently running in lab.

Installed the heater elements into their fixture and prepped the cables by twisting the wires into pairs. We also installed the pins onto the wires and placed them into the peek DB 25 connector. The installation tool we had did not fit the pin size we had so the pins needed to be installed by hand by opening the connector and holding them in place. In the future we will need to make sure we twist the wires together, group them, and then splice them all to the same size for easier installation. We then grouped all the twisted pairs into a bundle and zipped them together. On the left with two peek zip ties is the power and on the right is the RTD with one peek zip tie. This orientation remains true when looking at the feed through flange from the outside with the power port on closest to the wall.

We also installed the heater elements numbered 1-8 starting from the left in image 3. These elements have numbers as resistance data was taken before as to identify the heaters after they are in the chamber. After installing the DB 25 connectors we tested that the pins were in the right orientation by using a volt meter and testing the resistance where the cable runs into the the actual power supply. It seems that all the pins were properly installed and the resistance values all match with each one gaining about 2 Ohms from the cable itself.

Then the pump down was started. The pump was very slow and we suspected a leak but after changing the o-ring pump down was not any faster and we decided to leave it over break as it seemed to just be water outgassing from the aluminum. The chamber is now able to be RGA scanned and leak tested before the next bake as it is low enough pressure.

Below is the data for the most recent bake. I believe the chamber is cleaner than it is actually showing as the RGA data was still getting lower while the data was being taken. I will take the data again tomorrow just in case. Still, the data shows that the chamber is basically as clean as it was before bake 10 and this means further power testing can proceed.

Helium leak tested the chamber again today to check if the sealant changed anything. The two primary target flanges from last time have improved significantly with the flange from the RGA on the cross now being below 2e-14. While the turbo pump flange was leaking at a rate of 4e-13. Much better than what it has been before.

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.

slides

[Ma]

Installed all the pins to the peek DB 25 connectors

[Ma]

changed all zip ties to peek zip ties, and grouped wires together. The setup is ready to go into the chamber.

[Ma, Pooyan, Tyler]

On Friday, we connected the vacuum chamber with the Cymac.

1424039912.625576 2025/02/19 22:38:14 UTC Time start

24V 2.8A right after start all 8 elements

1424044804.902443 2025/02/19 23:59:46 UTC Time stop

24V 1.8A right before stop all 8 elements

0.1A right before start and right after stop

note: turned on briefly to check current right before stop

2/20 RGA Scan

spikes??

1424129207.857777 2025/02/20 23:26:29 UTC Time start

24V 2.9A right after start all 8 elements

1424140789.856096 2025/02/21 02:39:31 UTC Time stop

24V 1.7A right before stop all 8 elements

0.1A right before start and right after stop

2025/02/21 02:43:19 UTC

Main chamber pressure: 1.54e-8

RGA chamber pressure:5.06e-9

spikes are due to loose connection between connectors.

1424210410.173863 2025/02/21 21:59:52 UTC Time start

24V 2.9A right after start all 8 elements

1424218357.96404 2025/02/22 00:12:19 UTC Time stop

24V 1.7A right before stop all 8 elements

each elements: 0.3A (0.2A increment)(all)

0.1A right before start and right before stop

2/24 RGA Scan

1424467918.129082 2025/02/24 21:31:40 UTC Time start

12V 2A right after start all 8 elements

1424478936.635821 2025/02/25 00:35:18 UTC Time stop

12V 1.6A right before stop all 8 elements

each elements: 0.4A (0.2A increment)(all)

0.2A right before start

rise time: A(1-exp(-t/tau))+B

fall time: Aexp(-t/tau) +B

Continue investigation in the spikes

Pulsed ADC with a function generator and find no spikes. Rules out ADC for causing the spikes

Loopback test that bypasses the FROSTI Chassis shows spikes (spikes happened on all channels at the same time)

Next step is to bypass the AI Chassis to find the source of the spikes

The result from AI Chassis bypass test showed that the AI Chassis may be the problem. There are no spikes from DAC's direct output.

All chassis except timing chassis are turned off. Power supplies for 24V, 18V, and -18V are turned off

The AI chassis has been taken out of the rack for further inspection

https://dcc.ligo.org/LIGO-E2300117

https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?.submit=Identifier&docid=D2300124&version=

Test 1: Adapter Board Connected to Filter Board

• Setup: AI Chassis is powered on. Signal is measured directly from the adapter board. All other ports on the adapter board are connected to the filter board.
• Observation: Two distinct spikes observed at the beginning of the measurement.

Test 2: Adapter Board Disconnected from Filter Board

• Setup: AI Chassis remains powered on. Signal is again measured directly from the adapter board. This time, the remaining ports on the adapter board are not connected to the filter board.
• Observation: Multiple spikes observed, distributed evenly across the entire measurement.

Test 3: Isolation Test with Spare Adapter Board (ongoing)

• Setup: Suspecting the original adapter board may be faulty, a spare adapter board is used for comparison. Signal is measured directly from this spare board.

Update, 04/08/25, Tue 17:30

Took the old adapter board out of the AI chassis and and used it to connect DAC to AA chassis. If no spikes are seen, it means that the glitches are not originating from this board.

Also checked al the previous spikes using the raw data (65536 Hz sample rate). The duration of the glitches are ~1 second, despite the previous guess that they are happening in the Milli-second scale.

Test 4: AI Chassis ground isolation

• Setup: AI Chassis isolated from the ground with readout directly connected to adapter board
• Observation: No spike observed.

Test 5: Ribbon cable check

• Setup: AI Chassis remains isolated from the ground. The signal is measured after the ribbon cable. (Attachment 3)
• Observation: No spike observed.

Test 6: Single ground connection check

• Setup: AI chassis powered on but remains isolated from the frame. The signal is measured from the output of the AI Chassis. (Attachment 1 ,2)
• Observation: No spike observed.

Test 7: Reconnect ribbon cables

• Setup: Reconnect all the ribbon cables, and turned on the AI Chassis while isolated rack
• Observation: No spike observed.

Test 8: Reconnect to rack

• Setup: Reconnect the AI Chassis to the rack.
• Observation: No spike observed.

Test 9: Restore to original position.

• Setup: CLose up the AI Chassis, and put it back to its original location.
• Observation: No spike observed.

Using the configuration in section 2.11.1 in the Sorensen installation and operation manual (attached below), I'm able to remote control the Sorensen power supply.

I use DAC VEXC8 as the external voltage source and a breakout board to match the configuration of connector J3.

I have recorded 7 cycles (attached below), and am now working on analyzing the data.

We currently have the parts for a DB9 connector but need parts for a DB25 connector, where did we get the parts for the DB9 connector? We may be able to use the same company for the DB25 connector.

Also need a cable for the connectors. Find a DB9 to DB9 cable in 1129, not sure if I can disassemble it and use just the cable.

The pressure in the vacuum chamber rises to 2.12e-8 torr, which needs baking.

Date and Time: Around 3:50 PM on June 2, 2025

Location and Temperature:

• Back of the room 1119, around the working station: 86 °F
• Front of the room 1119, around the doorway: 84.1 °F
• Back of the room 1129, around the working station: 78.6 °F
• Front of the room 1129, around the doorway: 78.3 °F
• In the hallway in front of room 1119: 75.2 °F

By measuring the resistance of the ladder, I obtained a graph of resistance as a function of voltage.
All the heater elements behave consistently, showing only a small standard deviation.
However, heater element 5 shows a significantly larger standard deviation.
Upon examining the initial ladder graph, I noticed that the resistance of heater element 5 increases following a power outage that resets the system.
At this point, I am unsure why this behavior occurs.

CYMAC Remote Control Cable Assembly

Cable Functions

The custom cable assembly serves two primary functions:

Note: All connections are verified with a multimeter.

Note: This cable allows remote control of the Sorensen power supply with an external voltage source (Cymac DAC).

Note: For more details, check section 2.11.1 from the attached Sorensen power supply manual.

Slides

[Christina, Ma, Tyler]

Pomona Box completed and is now on the server rack in 1119. Additionally, the photodetectors were connected to the box and set up in front of the heater elements.

[Christina, Ma, Tyler]

Yesterday, Ma and I started taking data for the PSD/CSD measurements while the photodetectors and one of the heater elements are on (8) and are using the Red Pitaya to compare it to the data we took for the same measurements on the CyMAC. It will be finished Wednesday morning, and then we plan on starting to take additional recordings in order to conduct the same type of comparison for the dark noise measurements.

Date and Time: Around 4:50 PM on July 1, 2025

Location and Temperature:

• Back of the room 1119, around the working station: 85.7 °F
• Front of the room 1119, around the doorway: 83.5 °F
• Back of the room 1129, around the working station: 79.1 °F
• In the hallway in front of room 1119: 76.5 °F

[Ma, Christina, Tyler]

Figure 1 shows the following PSDs for channels 0-15 from the 14 hour test. Figure 2 shows the reduced chi squared and CSD plots for both the 2 Hz and 16 Hz resolutions.

[Tyler, Ma, Christina, Maple, Cece, Mary, Pooyan, Audrey]

We started by cleaning outside of the cleanroom wiping down the cable channel and working our way down while taking the pre-cleaning measurement. We then stated wiping down the inside of clean room and vacuumed, mopped the outside of the cleanroom. Finally, we vacuumed, mopped, and wiped down the floor inside the cleanroom.

Particle Count Measurements:

• Pre-cleaning (2:00 pm):
  • Zone 3:
    • 0.3 µm: 2707
    • 0.5 µm: 1374
    • 1.0 µm: 249
  • Zone 4:
    • 0.3 µm: 2207
    • 0.5 µm: 1166
    • 1.0 µm: 374

• Post-cleaning (4:30 pm):
  • Zone 3:
    • 0.3 µm: 4082
    • 0.5 µm: 2415
    • 1.0 µm: 708
  • Zone 4:
    • 0.3 µm: 1707
    • 0.5 µm: 791
    • 1.0 µm: 416

Date and Time: Around 4:20 PM on Auguest 6, 2025

Location and Temperature:

• Back of the room 1119, around the working station: 90.2 °F
• Front of the room 1119, around the doorway: 85.8 °F
• Back of the room 1129, around the working station: 93.4 °F
• Front of the room 1119, around the doorway: 82.3 °F
• In the hallway in front of room 1119: 77.2 °F