• Looked at the mode mismatch using cavity_mismatch_table().
• Compared these finesse_ligo factory model mismatch values with those of the aLIGO katscript model.
• The latter does not have the cavity_mismatch_table(), looked at both models' mismatch values using cavity_mismatch().
• Ascertained that there is less mode mismatch in the katscript model (~10^-2) as compared to the factory model (~10^-6).
• Mismatch values are starkly different, not just for (PRC, XARM) but also for others like (OMC, XARM).

• Analysed the locking process for factory model and katscript model to find minor differences in the order.
• Tried applying the katscript locking function to the factory model and still seem to get the same results. (to recheck)

[Ma, Mary, Tyler, Pooyan]

HEPA fan air flow measurements are done with the fans sitting on their side in the lab, and the anemometer being 24in away from the filter face of the fan. Per company's documents, we need to replace the filter if the air flow velocity drops under 38-45 fpm for the medium settings.)
 

All numbers are in fpm unit. The measurement for each unit is done twice in front of the fan positions.  

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

Slides discussing for A# Ring Heater design.

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

• concrete Caulk to fill the drill holes in 1119
  • Example [Pooyan: I have a caulk gun and silicon caulk at home, if needed.]
• Water hose for the washer in 1125
  • 1/2" diameter
  • almost 8 Ft 
• Exhaust for the oven in 1125
  • Question: not sure which way we want the exhaust to go. Measurements depend on the path. 
  • Oven exhaust to the ceiling vertical distance: 47"
  • Oven exhaust to the ceiling exhaust distance: 6 ft
• Rubber vibration dampers for the cleanroom fans (see the first 4 pictures)
  • 25 mm diameter, 13 mm height, ~5-6 mm thread, 6 mm deep
  • Example (This is the male version. We need one with female on both sides)
• Cabling conduit from the cable tray to the optical table frame (through the cleanroom ceiling)
  • Aluminum example
  • Galvanized Steel example 
• Wire cable tray for 1125
  • ~10 Ft, exactly similar to the one already installed in 1129

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.

[Pooyan, Ma, Mary, Tyler]

While re-installing the clean-room HEPA fan filters, we realized that one of the blowers is broken. The issue seems to be that the plastic damper bracket that is keeping the blower in place has failed. The fix is to open up the fan unit, and replace the broken vibration damper. We installed the defected unit on top of the clean room entrance, for easy future access.

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.

Vacuum Pressure Warning Script

Script Location: controls@chimay

Script Path: /vac/python/serial/temp_vacuum_warning.py

Purpose

Implement an automated warning system that monitors vacuum pressure and sends email alerts when pressure thresholds are exceeded.

Implementation Details

• The script runs launcher.py (located in the same directory) every 30 minutes to retrieve the latest vacuum pressure reading.
• If the pressure rises above the critical threshold (≥ 1 × 10^-6 Torr), an email alert will be sent to all group members.
• If the pressure rises above the warning threshold (≥ 1 × 10^-7 Torr), an email alert will be sent to Xuesi Ma.
• If launcher.py fails to retrieve the vacuum pressure, or if any execution error occurs, an error notification email will be sent to Xuesi Ma.

How to Run

python temp_vacuum_warning.py

Note

An app password is required for authentication in order to send alert emails.

[Cece, Ma, Mary, Pooyan, Tyler, Paul]

We have continued the reorganization of our Physics 1125 and 1129 lab spaces. This includes:

• Moving two workbenches from Room 1129 into Room 1125
• The workbench with the oven is still in Room 1129
• Assembling the stainless steel table
• Moving the cleanroom frame toward the whiteboard side to make room for HVAC work

The sink in Room 1125 was painted, and we stood Frosti up.

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

[Audrey, Cece, Jon, Ma, Mary, Michael, Pooyan, Tyler, Shane]

We have completed the preliminary reorganization of our Physics 1119 lab space. This includes:

• Moving all cabinets to their final positions
• Clearing out all equipment from the cleanroom in prep for HVAC work, and storing them in either the HEPA cabinet or double-bagging in regular storage.
• Moving all non-essential equipment into other lab spaces.
• Wrapping vacuum system and VLC for protection
• Removing all ceiling tiles and fans from the ceiling of the cleanroom
• Moving the cleanroom frame towards the front of the room.

Prepping the new clean-and-bake station in 1125 will begin within the next week, along with the construction of the stainless steel table planned to be put into the cleanroom.

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

The working document of tasks regarding moving the clean room is attached. Needs LIGO account to access and edit.

  https://docs.google.com/document/d/14HhMYBcHmM62Hc1YJhinMsG5uPx6xoW0WEBmDcbNMMg/edit?usp=sharing

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