= ISC Meeting on 2016/10/17 14:00 - 15:00 = Participants: Michimura, Kambara, Aso, H. Yamamoto, Arai, Miyamoto, Somiya, Kokeyama, Akutsu, Inoue === Next meeting === 2016/11/2 14:00 - 15:00 [[LCGT/subgroup/ifo/ISC/Meetings|back to Meetings page]] == Minutes == * Arm Length Stabilization Noise``Budget [Kambara] [[attachment:ISCMeeting20161017_Kambara.pdf]] * optical fiber wiring plan presented * cable racks at clean booths might be too loud * consider using racks on tunnel wall, use lower rack first * ask LIGO people how they are fixing the cables * local oscillator phase noise calculation ([[https://granite.phys.s.u-tokyo.ac.jp/wiki/Lab/index.php?LCGTALSPhaseNoise|calculation method]]) * discuss with Aso and redo calculation [Kambara] * Cryopayload actuator simulation [Miyamoto] * if low power coil driver is used for TM, actuator efficiency should be less than 1.5 mN/A from noise point of view * 3-stage whitening filters are already considered * 2 mm dia. 2 mm thick Sm``Co with 600(500?)-turn coil gives 15 mN/A * if 1.5 mN/A, RMS velocity should be smallter than 0.04 um/sec * simulation on-going [Okutomi] * marionette moving mass * resolution is 0.4 urad in pitch * this is small enough compared with IM, MN actuator range (+/- 12 urad) * range is +/- 24 mrad * this is large enough compared with tilt induced by 10 % difference in fiber length change during cool down (< 3 mrad) * Cameras for ETM HR surface [Inoue; after the meeting] * considering integration time, latency will be roughly ~ 1 min for ~2 W operation (Pcal beam, bKAGRA Phase 1 main beam) * put mirrors on narrow angle baffle holder to see ETM HR from the camera * wide angle baffle modification is needed to see the ETM edge * another option is to directly see ETM HR from a small hole on narrow angle baffle holder == Agenda == * MIR update [Hirose] * coated PRM transmission acceptable? {*} * required spec was 10 +0.1 % / -0 %, but measured value was 10.35 % * MIF group concluded that this is acceptable according to LSC/ASC shot noise calculation [[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5744|JGW-L1605744]] * bKAGRA Phase 1 optical configuration study [Michimura] * summary: [[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5595|JGW-T1605595]] * ASC [Enomoto] * noise study by Noise``Budget [Enomoto] * Enomoto volunteered to do ASC Noise``Budget; meeting on Sept 27 * trouble on number of licenses and library links, but finally able to run example model * 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]: [[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5595|JGW-T1605595]] * procedure summarized in [[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5692|JGW-T1605692]] {*} * presented at Chief Meeting on Sept 26 * '''TMS BRT alignment could be tough''' because of dim transmitted beam after ETM installation * use green? * '''check optical layout [Michimura->Aso]''' * check if ETM transmitted beam can go through when ETM is not installed [Michimura] {*} * ETM transmitted beam can reach EXT/EYT when no wedge (5.6 mm shifted from the center of EXT/EYT) * EXT/EYT tanks/ducts are installed considering ETM wedge effect * wide/narrow angle baffles for Phase 1? [Akutsu] {*} * talk with Uchiyama & Saito on Sept 27-28? * as for NAB: install if possible, but maybe without suspension * as for WAB: try WAB with suspension at EXC, maybe no installaton at EYC * first priority is cryopayloads and evacuation/cool-down * discussion on camera to see ETM HR surface started [Akutsu, Inoue, Kokeyama] {*} * start with a plan to use viewport at EXA/EYA * baffle design have to be modified to see the edge of ETM * meeting at Kamioka on Oct 5 [Akutsu, Inoue, Kokeyama] * CAL report ([[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5737|JGW-G1605737]]) * how to extract AS beam should be fixed by MIF * extract SR2 reflected beam at SR3 chamber {*} * IMMT1-IMMT2 beam collimation plan not yet [MIF] * green alignment plan not yet [MIF] * 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 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) -> 6 arrived (Mozumi office loft), 4 not yet arrived (by mid-November?) {*} * 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 [[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 * 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? [[https://dcc.ligo.org/LIGO-D1002178/public|LIGO-D1002178]] * photos arrived [[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5492|JGW-T1605492]] {*} * RF PDs and RF QPDs * RF PD / RF QPD noise and transimpedance characterization [NiigataU?] * need to check RF QPDs for IMC WFS, by the end of Oct 2016 * IR LED is at Kamioka, no network analyzer at Kamioka (one at Toyama U and the other at Kashiwa) * 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] ([[KAGRA/Subgroups/IOO/OutputTables|OutputTables wiki]]) * 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 * '''make budget estimate and send it to Kawamura'''　[Michimura] * EXT/EYT tables * '''get foot positions and send it to Saito''' [Michimura] * 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) * 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 * local oscillator phase noise, optical fiber wiring {*} * Magnetic noise, actuator noise calculation for cryogenic payload * magnetic noise [[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=4459|JGW-T1504459]] [Shimoda] * actuator noise and range calculation on going [Miyamoto([[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5746|JGW-G1605746]]), Okutomi] {*} ----- * Requirement on actuator range for IMMT [Ohishi] {*} * magnet size: 2 mm dia, 5 mm long * coil turns: 39? * this gives 4 times larger efficiency than the IMC coil efficiency * IMMT resonant frequencies: pitch ~1.8 Hz, yaw ~1.5 Hz * this gives 50/sqrt(2) mm * (1.4e-3 N/A * 4) * 4 magnets * 1/80 A/V / 9.6e-4 kg*m^2^　 / (2*pi*1.8 Hz)^2^ = 8e-5 rad/V efficiency in pitch * is this enough? * IMC mirror (Type-C + stack) drift in yaw was less than 1 mrad/month, pitch was much less [Nakano] * iKAGRA ETM (Type-C w/o stack) drift was ??? * 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 ([[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5493|JGW-T1605493]]) * MIF agreed to use 32 MHz and 33 MHz for ALS sidebands [[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5626|JGW-T1605626]] * may be IMC sideband (and ALS sidebands) should also needs to be phase locked with f1/f2/f3 to avoid "whistling noise" * 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] * 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] * 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: [[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]''' * OFI, OMMT, OMC meeting on 2016.9.14 * design suspended table similar to TMS? {*} * Task list update ([[KAGRA/Subgroups/MIF/TaskList|TaskList]]) [Michimura]