ISC Meeting on 2016/9/20 14:00 - 15:00
Participants: Michimura, Aso, Enomoto, Akutsu, Haino
Next meeting
2016/10/17 14:00 - 15:00
Minutes
bKAGRA Phase 1 commissioning JGW-T1605595
- UPDATE: no PR-related adjustments before Michelson operation
- Arai and Aso agreed
- MIF recommend not to install Pcal at Phase 1 considering tight schedule
check if transmitted beam can go through when ETM is not installed [Michimura -> Saito, Uchiyama, Kimura]
- check if EXC-EXT (EYC-EYT) ducts are installed considering ETM wedge
- wide/narrow angle baffles for Phase 1?
- install if schedule permits; check with Uchiyama [Akutsu]
- INTERFACE: Pcal and narrow angle baffles
- how to see the HR surface of ETM? [Akutsu, Inoue]
- we need to see ETM HR surface for the beam alignment and Pcal spot position monitor
- we have viewports to see HR surface at 45 deg; but wide angle baffle can be an obstacle
- holes for wide angle baffles?
- camera with telescope from EXA/EYA?
since angle is too narrow, scattering maybe too low, and cannot see from cameras? -> calculation [Akutsu]
- UPDATE: no PR-related adjustments before Michelson operation
- bKAGRA Phase 1 electronics
- electronics for IMC WFS are most urgent (we need them by the end of Oct 2016)
- RF amps for Distribution Amplifier not yet arrived
- need to check RF QPDs [Niigata U?]
- IR LED is at Kamioka, no network analyzer at Kamioka (one at Toyama U and the other at Kashiwa)
- still, we can tune the resonance with IR LED or test inputs
- electronics for IMC WFS are most urgent (we need them by the end of Oct 2016)
- Aperture of sapphire test mass
- recoil mass aperture is OK for diffraction loss and scattering noise
- what is the baffle aperture?
see Fig 2 of Optical Materials Express 6, 1613 (2016)
- #1 arm-duct baffles 720 mm dia.
- #2 cryo-duct shields 270 mm dia.
#3 narrow angle baffles 254 mm dia. JGW-D1504223
#4 wide angle baffles not decided
- if smaller than 169 mm, loss will be larger than 10 ppm, and should be considered
- if larger than 191 mm (larger than recoil mass aperture), no problem at all
- MIR update [Hirose via Email]
test plate of IMMT1 was characterized; modifying RoC a little for IMMT1&2 based on the information
- coated optics will be characterized once they finish coating
Agenda
- bKAGRA Phase 1 optical configuration study [Michimura]
summary: JGW-T1605595
- UPDATE: no PR-related adjustments before Michelson operation
- 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-T1605595
- 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;
- Oct 31, 2017: ETMY CRYp installation done
- Dec 8, 2017: ETMY cool down starts
- Feb 13, 2018: ETMX CRYp installation done
- Mar 2, 2018: ETMY cool down starts
we need more time for PR-ETMY cavity
- no more PR-ETMY cavity before Michelson operation
- 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]
- beam profiling plan should be compatible with vacuum plan; MIF will lead the planning
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) -> not yet arrived (by the end of Sept?)
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
- photos of the assembled chassis are helpful for AEL
- Quad IQ Demodulator heat-up issue
- 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, SEO agreed, next step is budget migration
- 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)
- fiber length? how to do the wiring?
- 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
- 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]
- OFI, OMMT, OMC meeting on 2016.9.14
- design suspended table similar to TMS?
- Magnetic noise, actuator noise calculation for cryogenic payload [Michimura]
Ask Tomaru about the parameters and actuator design, range
Task list update (TaskList) [Michimura]