In-vac PD/QPD layout meeting 2025/12/23
Time: 14:00-14:30
Participants: Huali Chen, Ryan Yang, Ray-Kuang Lee, Yoichi Aso, Yuta Michimura
Zoom meeting
Minutes
Notion AI minutes: https://www.notion.so/In-vac-PD-Optical-Layout-Meeting-2d243f9c5c60803ab520e13762ca6c72
- POP design (Ryan)
- POP in-vac/in-air design completed
- POP Forward in-air design completed
- Green X design updated with correct lens parameters, but the position of the waist shifted due to space constraints
- Check mode-matching to X arm
According to v9: https://gwdoc.icrr.u-tokyo.ac.jp/DocDB/0096/T1909623/009/20220407_KAGRA_POP.svg
- RLNS2 f=500mm
- RLNS3 f=-100mm
- According to Nakagaki-san's photo from 2023
- GLNS1 f=150mm
- GLNS2 f=100mm
- GLNS3 f=100mm
- GLNS4 f=200mm
- GLNS5 not lens but probably just an iris
- In-vac periscope (Ryan)
New design following LIGO-D1002350 is ongoing. See JGW-D2517008.
- The top mirror height is 200 mm, and the lower mirror height will be 4 inch - 15 mm.
- Updated the mirror holder design, and did FEM resonant frequency analysis for each component
- Lowest resonant frequency being ~1 kHz
A/I
- Consult with VAC people to start designing REFL/POP PD tank [Yuta]
- Send Ryan information on arm cavity parameters for green X mode matching calculations [Yuta]
- Upload the latest REFL and POP optical layout design, with ppt files describing the details of the design [Ryan]
- Update the periscope beam dump design [Ryan]
- Send Ryan information on the angle for the beam dump [Yuta]
- Adjust the QPD base plate design for OMC chamber [Ryan]
- Prepare for the review for in-vac periscope and QPD base plate [Ryan]
- Include FEM resonant frequency information and weight information
What to do with a beam diverter? -> NAOJ ATC will take care, with responsible persons being Michimura and Akutsu
- Next meeting: will be a review for in-vac periscope and QPD base plate
