= ISC Meeting on 2017/3/13 14:00 - 15:00 = Participants: H. Yamamoto, E. Hirose, K. Somiya, K. Izumi, T. Akutsu, K. Arai, H. Tanaka, Y. Michimura === Next meeting === 2017/3/27 14:00 - 15:00 [[LCGT/subgroup/ifo/ISC/Meetings|back to Meetings page]] == Minutes == * Magnetic noise measurement inside cryostat [Tanaka] * results from spectrum analyzer and data logger didn't matched, but confirmed spectrum analyzer is reliable (data logger had aliasing issue) * measured noise is roughly 3 pT/rtHz @ 10 Hz, limited by the sensor noise * send the data to Michimura [Tanaka] * OFI and OMC status ([[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=6334|JGW-T1706334]]) [Somiya] * new AS optics layout: SRM -> OMMT1 -> OMMT2 -> OFI -> STM -> OMC * look for OFI with larger aperture [Somiya] * OMC alignment: use STM and OMMT2? we need more aperture for OFI * for redundancy, OMC should be actuated also * be careful of magnetic field by OFI; OMMT1 is close and alignment might change * maybe we need a prototype OMC to be installed at first stage to practice alignment, servo and so on * prototype could be made with a metal plate (or carbon plate?) * anyway, real OMC should be purchased in next FY. * MIF should request budget for next FY == Agenda == * Recent activities in Kamioka * TRX, TRY optical tables delivered ([[http://klog.icrr.u-tokyo.ac.jp/osl/?r=2531|klog #2531]], [[http://klog.icrr.u-tokyo.ac.jp/osl/?r=2538|klog #2538]]) * 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 * POS and AS tables * table height fixed; POS will be on concrete surface, AS will be on mortar surface * installation on Mar 23 {*} * OFI status [Somiya] * any updates? * Actuator noise modeling [Michimura,Miyamoto] ([[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=6333|JGW-G1706333]]) {*} * now included quantum noise and magnetic noise ([[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=3453|JGW-T1503453]]) * how to treat feed forward? * do we use ALS DIFF or IR DARM quantum noise for ETMs? * actuator design for cryogenic payload ([[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5938|JGW-G1605938]]) * magnets for Marionette too small? ([[KAGRA/Subgroups/VIS/ActuatorDesign|ActuatorDesign wiki]]) * magnetic noise [[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=4459|JGW-T1504459]] [Shimoda] * meeting on March 14? * What can we do now? {*} * RF PD/QPD characterization * electronics and cabling diagram * RT modeling, MEDM screens, guardian scripts * better modeling (Optickle, Finesse, FFT, Noise``Budget, etc.) for ALS and intermediate configurations * RF generation scheme, RF AM generation scheme * AS optics (OMC, OFI, OMMT) * initial alignment planning * in-vacuum optics/electronics design ----- * 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 faint transmitted beam after ETM installation (~0.25uW) * use green? * BS transmission for green is S:99.40% P:97.85% at 45 deg * 100 mW green beam from PR gives ~0.12 mW at ETMY transmission * '''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 * how to peel off the first contact? * we cannot see the beam on ETM with IR cards with WAB * first priority is cryopayloads and evacuation/cool-down * camera to see ETM HR surface [Akutsu, Inoue, Kokeyama] {*} * CAL report ([[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5737|JGW-G1605737]]) * wide angle baffle modification is needed to see the ETM edge * how to extract AS beam should be fixed by MIF * extract SR2 reflected beam at SR3 chamber (decided at the meeting on Sept 13) {*} * Layout around SRs ([[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5967|JGW-T1605967]]) * IMMT1-IMMT2 beam collimation plan not yet [MIF] * green alignment plan not yet [MIF] * TMS possible without ITM? [Akutsu->Michimura] * check q-parameter at TMS witouht ITM * 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''' * Quad IQ Demodulator LSC to ASC<
> * 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 [[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=4460|JGW-D1504460]] * we will omit RF monitor for now, and add them later * front/rear panels, RF amps, 8-way splitters, couplers, cables and connectors at Mozumi office loft * RF Frequency Doubler * what's the frequency? [Kamiizumi->Michimura] {*} * thought used for 2*f1,2*f2, but aLIGO uses them for ALS * Requested Universal Whitening Filter with DC Power to AEL ([[http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5839|JGW-T1605839]]) {*} * see [[KAGRA/Subgroups/AOS/DCQPDDriverList|DCQPDDriverList]] (see, also, [[KAGRA/Subgroups/AOS/DCQPDList|DCQPDList]]) * need to coordinate with subgroups (MIF, IOO, AOS, VIS, CRY) * RF PDs and RF QPDs * RF PD / RF QPD noise and transimpedance characterization * we need permanent test bench * 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 * 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? {*} * ask LIGO people how they are fixing the cables {*} * no special vibration / heat treatment [from Kawabe] * 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 ([[https://granite.phys.s.u-tokyo.ac.jp/wiki/Lab/index.php?LCGTALSPhaseNoise|calculation method]]) {*} * discuss with Aso and redo calculation ----- * 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" * in case of KAGRA, we don't need Frequency Doubler or Frequency Divide By Two for ALS {*} * is this true? * 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] * 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 is TMS-like plate spring and single pendulum [Somiya] * Task list update ([[KAGRA/Subgroups/MIF/TaskList|TaskList]]) [Michimura]