Cleaned off the tapes on the optical table with acetone.

DetChar meeting presentation

[Tyler, Ma]

We suspect a pressure gauge problem. The electronic unit of the main chamber pressure gauge and the electronic unit of the RGA chamber pressure gauge are swapped.

Power and current draw aren't high for the turbo pump.

Before opening the gate valve, the pressure in the Main chamber is 2.98e-8 Torr, RGA Chamber 1.21e-5 Torr

After opening the gate valve (not fully open), the pressure in the Main chamber is 2.97e-8 Torr, RGA Chamber 1.55e-9 Torr. Note: the HV sensor suddenly turned on and the reading jumped to -9 Torr

Opening the gate valve a bit more, the pressure in the Main chamber is 2.98e-8 Torr, RGA Chamber 1.34e-9 Torr.

After switching the electronic unit, the pressure in the Main chamber is 3.23e-8 Torr, RGA Chamber 1.43e-9 Torr.

Gate Valve fully opened at 16:01 Oct 24, 2025

Action items for facilities

• Ceiling lights replacement
• Fume hood cleaned and refurbished
• Sink countertop cleaning
• Floor cleaned and waxed
•  

Below are slides discussing RIN infrastructural updates related to the CyMAC.

Slides

Below are slides giving an update on RH O6 design progress.

These are the frequency averaged and veto binned plots for the initial Red Pitaya and CyMAC systems.

Updated CyMAC measurement, comparing 260 hrs of measurement time vs. 405 hrs.

[Ma, Tyler, Christina]

This past week, we were able to set up the data streaming for continuous acquisition to the PCs, and can conduct the initial tests now. We were able to do this by:

• Installing the correct OS ecosystems to each Red Pitaya
• Installing the terminal streaming client
• Debugging formatting and file saving issues by saving the data in a TDMS file on the host PC.

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

Simulating how point absorber defects on Advanced LIGO mirrors affect cavity performance by modeling a 4km LIGO-like arm cavity with a point absorber fixed at 5cm off-center on the ITM. In this simulation, displaced the laser beam across a 21×21 grid while calculating the deformation, then measuring the resulting power loss in the cavity (~283W circulating power).

[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

[Ma, Christina, Tyler]

ADC CyMAC 260 hr, 8192Hz sampling rate channels V3 and Vref6

[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.

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