ISC Meeting on 2016/9/20 14:00 - 15:00

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2016/10/17 14:00 - 15:00 ??

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Agenda

bKAGRA Phase 1 optical configuration study [Michimura]
- summary: JGW-T1605595
- ASC [Enomoto]
  - noise study by NoiseBudget [Enomoto]
    - Enomoto volunteered to do ASC NoiseBudget; meeting on Sept 27
  - effect on WFS from RF HOMs [who?]
- check if reference spheres for PR mirrors are available at Caltech [Hirose]
  - 9.0m (CC), 11.5m (CC), 6.5m (CC), 5.0m (CC), 34m (CX), 36m (CX) were available
  - PR2/SR2 is -3.0764m/-2.9872m and PR3/SR3 is 24.9165m. Maybe 5.0m TS can be used for PR2/SR2.
  - what about PR3/SR3, PRM/SRM?
- check if IMC length stability and others are compatible with 3-km PRMI [Michimura]
bKAGRA Phase 1 initial alignment / commissioning plan [Michimura]: JGW-T1605274
- beam profiling plan should be compatible with vacuum plan; MIF will lead the planning
  - not only PR2-PR3 but also IMMT1-IMMT2
- how to extract AS beam should be fixed by MIF
- according to CRYp current schedule;
  - Nov 1, 2017: ETMY CRYp installation done
  - Nov 21, 2017: ETMY cool down starts
  - Feb 2, 2018: ETMX CRYp installation done
  - Feb 19, 2018: ETMY cool down starts
- we need more time for PR-ETMY cavity
  - negotiate with CRYp to fix ETMY cooling schedule
- do we have enough time for TMS measurement and PR2-PR3 adjustment?
- initial alignment plan including green is taken cared by MIF [confirmed with Kawamura, Moriwaki on Aug 30]
bKAGRA Phase 1 analog electronics (Analog Electronics for ISC) [Michimura]
- Quad IQ Demodulator heat-up issue
  - 1st stage amp is heating up
  - we have to decide if we need 1st stage amp or not
- remake of Quad IQ Demodulator LSC to ASC [Michimura->Niigata students?; by 2016.10]
  - MIF will take care instead of AEL
  - mass production will be taken care by AEL
  - 4-way splitter (Mini-Circuits ZFSC-4-1-S+) arrived at Kamioka -> Mozumi office loft
- RF Distribution Amplifier [Michimura->Niigata students?; by 2016.10]
  - we will omit RF monitor for now, and add them later
  - Nakano found front/rear panels -> Mozumi office loft
  - ordered RF amp (Wenzel LNBA-11-23-CK-100-15)
  - 8-way splitter (Mini-Circuits ZCSC-8-1+), coupler (Mini-Circuits ZX30-20-4) arrived at Kamioka -> Mozumi office loft
  - cables and connectors to assemble one chassis by hand arrived at Kamioka -> Kokeyama's desk
  - basically copy of LIGO-D1000124, but we will omit Interface for the first stage
  - asked AEL to make RF amplifier interface board (which is also used for Frequency Doubler) [Michimura]
- RF Patch Panel modification [Michimura->Niigata students?]
  - one by one by hand is tough; outsource?
- Electronics request meeting with Miyakawa/Kamiizumi on Aug 24
  - photos of the assembled chassis are helpful for AEL
    - does anyone have a photo of Frequeny Doubler? LIGO-D1002178
      - asked Izumi and Kokeyama
RF PDs and RF QPDs
- RF PD / RF QPD noise and transimpedance characterization [who?]
- RF PD modification [who?]
  - fix DC path
  - solve single supply issue (RF PDs easily break when accidentally supplied with single)
  - fix plugs so that Dsub 9pin cable fixes better
Output optical tables [Michimura] (OutputTables wiki)
- Kawamura suggested to move this task from IOO to MIF
- vacuum optics to extract beams for each port (except for REFL and AS DC) and related beam shutters will also be MIF task
- MIF and IOO agreed, waiting for SEO to agree
RF generation scheme [Michimura]
- f1 = 3/8*f2, f3 = 10/8*f2
- we need 2*f1, 2*f2, f3-f1, f3-f2 as well
- use harmonics generator (x2, x3, x6, x8, x10, x16 for f2/8 = 5.62698725 MHz (FSR for IMC))
  - seeking for vendors
- MIF and IOO agreed to use 13.78 MHz　(~= f2/8*2.45) for IMC sideband (JGW-T1605493)
- MIF agreed to use 32 MHz and 33 MHz for ALS sidebands JGW-T1605626
- may be IMC sideband (and ALS sidebands) should also needs to be phase locked with f1/f2/f3 to avoid "whistling noise"
Arm Length Stabilization plan (JGW-T1605353)
- NoiseBudget [Kambara]
  - results agreed with Tatsumi Simulink model
  - include fiber noise (fiber setup is different from Tatsumi model)
  - include phase noise from mirror vibration for IR beat setup (it is one of the limiting noise source for aLIGO)
  - schedule and plan for the procurement of circuits should be fixed soon
    - keep in touch with AEL group

Aperture of sapphire test mass
- recoil mass aperture is OK for diffraction loss and scattering noise
- what is the baffle aperture?
bKAGRA optical layout around PRC
- POY clipping issue will be solved by modifying PR3 optical bench suspension [Shoda]
- we need layout CAD for POY pickoff mirror, POP pickoff mirror to design baffles
  - budget for baffles around POY and POP were shifted to next FY [SEO]
iKAGRA post-run calibration mystery [Aso]
- mysterious LPF was from saturation (elog #1958)
Requirement for the noise of watchdogs for coil drivers [Aso]
- recent result show dR < 1e-7 Ohm/rtHz, so it may meet the requirement
- slow (~20 min) drift at dR ~ 5e-4 Ohm -> this should be negligible
Viewport quality for GV between SRM and OMMT [Akutsu]
- aLIGO case: SRM-OFI-viewport, KAGRA case: SRM-viewport-OMMT-OFI
- aLIGO viewport is always closed
- if we need super quality viewport, we have to decide soon
BS baffle could make contract defect? (LIGO-T1000090)
- ask Akutsu and Hiro
- BS has 370 mm dia and beam at BS is 2*36 mm dia. So, it should be in principle OK. But recoil mass aperture should be considered.
bKAGRA ISC cabling [Michimura/Doi]
- announced to IOO mailing list
- need to update the cabling diagram
Mirror absorption measurement status [Hirose]
Output optics status [Somiya]
- suspensions for OMMT1/2 is same as IMMT1/2 (driver list for now: JGW-L1605334)
- we have to make vacuum compatible PD/QPD for OMC by 2018.3
- beam shutter: prototype done, AR coating and driver circuit design not yet
- OMC suspension requirement cross check [Somiya]
Magnetic noise, actuator noise calculation for cryogenic payload [Michimura]
- Ask Tomaru about the parameters and actuator design, range
Task list update (TaskList) [Michimura]