ISC Meeting on 2017/6/19 14:00 - 15:00
Participants: (eZuce meeting)
Next meeting
2017/7/3 14:00 - 15:00
Agenda
PSL EOM Layout re-consideration [Enomoto] (JGW-T1706748)
- Delay-line length decided to be 2.66 m (instead of 8.88 m)
- Modulation phase between f1 AM and PM is always aligned (we need this to be aligned)
Modulation index needed at each EOM is less than measured maximum index by Uehera (JGW-T1605611)
- Optickle simulation by Kohei Yamamoto
- simulation on imperfections (MZ arm asymmetry, MZ lock, EOM phase difference control etc.)
- start with hand calculation, simple setups, and then to full IFO simulation
- meeting with him on June 6.
- Requirement on carrier power loss?
Comment from Stefan Ballmer
- Similar calculation was done in LIGO in the past. Displacement noise requirement for MZ was tough (~1e-14 m/rtHz).
- Any in-air interferometer suffer from jitter and frequency noise which cannot be suppressed.
- OFI and OMC status? [Somiya]
- look for OFI with larger aperture [Somiya]
- output optics task sharing status?
- OMC baseplate issue?
design review on June 26 at Titech
Actuator noise modeling [Michimura,Miyamoto] (JGW-T1503453)
Updated magnet size for cryopayload marionette (ActuatorDesign wiki)
Updated lock acquisition section to derive velocity requirements for suspensions (see ISC Meeting minutes 20170410) [Michimura]
- Needs to implement frequency noise, but FSS modeling with ALS is complicated [student!]
Paper?
bKAGRA Phase 1 initial alignment / commissioning plan [Michimura]: JGW-T1605692
- updated based on current schedule
- ETMX and ETMY cryopayload installation almost at the same time
- MICH lock at room temperature before cooling down (instead of cooling down ETMY first)
- AS cannot be used for room temperature MICH lock (SR3 not ready)
- SR2 won't be ready by the end of March 2018
- Fixed mirrors for AS port (including SR2)
- Some comments from the Chief Meeting
- Revised schedule seems compatible with PRMI. Why not?
PRMI is an option after achieving the Phase 1 goal, if it doesn't delay the final bKAGRA JGW-T1605595
- Initial alignment does not interfere with ITM Type-A installation work?
- Evacuation of IXC/IYC compatible with Type-A installation work?
- Initial alignment compatible with Pcal setup at EXA/EYA?
- Meeting with Inoue on June 15
- Revised schedule seems compatible with PRMI. Why not?
- updated based on current schedule
IR/green steering mirrors [Michimura]
- for POP/POS and green steering in PR2/SR2 chamber, needs picomotors and ~40 cm pedestals
- need this by the end of August 2017 (after PR2 installation on June, before IR initial alignment starts on September)
- proposed mirror specs
- HR reflectivity: more than 99% for both 1064nm and 532nm
- AR refectivity: less than 0.3 % for 1064nm, similar for 532nm
- incient angle: 20-45 deg, s-polarization
- radius of curvature: flat
- size: 2-inch
- wedge: 1 deg
- substrate: Fused Silica
- surface quality: λ/20, 0.1 nm rms roughness
See this page for other agendas.