= ISC Meeting on 2016/8/22 14:00 - 15:00 = Participants: Michimura, Aso, Enomoto, Arai, Kambara, Moriwaki, Akutsu, Hirose, (Kawamura) === Next meeting === 2016/9/5 14:00 - 15:00 [[LCGT/subgroup/ifo/ISC/Meetings|back to Meetings page]] == Minutes == * bKAGRA Phase 1 TMS/mode measurement [Enomoto] * by measuring the beam radius at ETM, g-factor can be measured within precision of ~0.09; not enough * more precise measurement can be done using transfer function measurement with injected sidebands trough IMC (see [[https://dcc.ligo.org/LIGO-G080467|LIGO-G080467]]) * consider using this technique * it takes only few minutes to adjust PR2-3 length (even in vacuum) [Aso] -> confirm with Shoda again [Michimura] * bKAGRA Phase 1 analog electronics [Michimura] * MIF agreed on recent electronics request to AEL * Output Optics Table [Michimura] * MIF group agreed to move this task from IOO to MIF * needs agreement from IOO group and then from SEO * safety issue on 2 W beam exposure in air should be discussed * RF generation scheme [Michimura] * IMC sideband frequency ([[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5493|JGW-T1605493]]) * MIF agreed to use f2/8*2.45 = 13.78 MHz for IMC sideband * needs agreement from IOO group also * may be IMC sideband (and ALS sidebands) should also needs to be phase locked with f1/f2/f3 to avoid "whistling noise" * it could be easily done with N5181A, but maybe not with VCXO(OCXO?) to be used in the future * Noise``Budget for green lock [Kambara] * fiber noise was added (see [[https://dcc.ligo.org/LIGO-T0900376|LIGO-T0900376]]) * Prometheus laser noise was updated to use spec from Coherent * real SHG noise is not available yet -> ask Kawabe/Izumi [Kambara] * Updates from MIR group [Hirose] * availability on reference spheres for PR mirrors will be checked this week at Caltech * AR aperture is 204 mm dia for sapphire mirror * this size is tolerable considering 35.3 mm beam radius on ITM/ETM and 2.7 sigma (1 ppm loss) * aperture of recoil mass should also be checked [Michiura->Tomaru] == Agenda == * bKAGRA Phase 1 optical configuration study [Michimura] * HOM structure / ASC check [Enomoto] ([[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5362|JGW-T1605362]]) * decided to move PR2/3 by 1.20 cm -> confirm with Shoda again [Michimura] * Shoda said 1.20 cm is OK * Now the question is how long does it take to adjust it again -> asking Shoda * even if we move by 1.20 cm, PRMI is still unstable in worst RoC error case * effect on WFS from RF HOMs should be [who?] * feedback topology and noise study should be done [Enomoto?] * how to measure the g-factor? PRMI cavity scan possible? * need to make beam profiling plan [Enomoto] * check if reference spheres for PR mirrors are available at Caltech [Hirose] * check if IMC length stability and others are compatible with 3-km PRMI [Michimura] * bKAGRA Phase 1 initial alignment / commissioning plan [Michimura]: [[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/DocDB/ShowDocument?docid=5274|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 * CRYp agreed on installing ETMY earlier by two months (ETMY CRYp: 2017.8-9, ETMX CRYp: 2017.12-2018.1) * use 2017.10-11 to test PR-ETMY and ETMY cooling * '''negotiate with CRYp to fix ETMY cooling schedule''' * bKAGRA Phase 1 analog electronics ([[KAGRA/Subgroups/MIF/AEL|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 istead 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 * '''where did front/rear panels go?''' -> look for them on Aug 24 [Nakano] * 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 * basically copy of [[https://dcc.ligo.org/LIGO-D1000124/public|LIGO-D1000124]], but we will omit [[https://dcc.ligo.org/LIGO-D1000064/public|Interface]] for the first stage * ask LIGO people for necessity of RF monitor [Michimura] * RF monitor was used in aLIGO for noise hunting and IFO health check (input from Izumi) * '''we have to request AEL to make interface board''' * RF Patch Panel modification [Michimura->Niigata students?] * one by one by hand is tough; outsource? * Requested to AEL; meeting with Miyakawa on Aug 24 [Michimura] * Quad IQ Demodulator LSC [[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5487|JGW-T1605487]] * Quad IQ Demodulator ASC [[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5488|JGW-T1605488]] * High Power Coil Driver [[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5489|JGW-T1605489]] * RF Distribution Amplifier [[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5490|JGW-T1605490]] * Common Mode Servo Board [[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5491|JGW-T1605491]] * Frequency Doubler [[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5492|JGW-T1605492]] * Output optical tables [Michimura] ([[KAGRA/Subgroups/IOO/OutputTables|OutputTables wiki]]) * '''Kawamura suggested to move this task from IOO to MIF''' * Is it acceptable? * 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 * '''sideband frequency for IMC? (should be determined before EOM production; by the end of 2016.8)''' * f2/8*2.45 = 13.78 MHz for IMC anti-resonance? ([[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5493|JGW-T1605493]]) * Arm Length Stabilization plan ([[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5353|JGW-T1605353]]) * Noise``Budget [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 ----- * 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 * '''possibility of buying baffles next FY? -> ask SEO [Aso]''' * ask SEO to hire a person dedicated for optical CAD * layout CAD will be prepared by each subgroup for the time being * iKAGRA post-run calibration mystery [Aso] * mysterious LPF was from saturation * '''write an elog about this conclusion [Aso]''' * 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? ([[https://dcc.ligo.org/LIGO-T1000090|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] * need to announce to IOO,ISC mailing list; e-mailed to Doi-san for go sign * Mirror absorption measurement status [Hirose] * Output optics status [Somiya] * suspensions for OMMT1/2 is same as IMMT1/2 (driver list for now: [[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5334|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 ([[KAGRA/Subgroups/MIF/TaskList|TaskList]]) [Michimura]