= O4 Commissioning Task List = This is a list of things to do for each commissioning stage for O4. Each stage include ASC. === References === * klog review during O3 commissioining [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=12729|JGW-E2112729]] * [[KAGRA/Subgroups/MIF/OpticalCharacterization|Summary of Optical Characterization]] * Commissioning (IOO): Evaluation meeting [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=12491|JGW-G2112491]] * MIF Schedule Estimate for bKAGRA Phase 2 [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=7079|JGW-T1707079]] * Definitions for the X arm commissioning [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=8343|JGW-T1808343]] * Definitions for the DRMI commissioning [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=9573|JGW-T1909573]] === Priority legend === * [A] High priority and/or easy to do * [B] Medium priority and/or preferable to do * [C] Low priority and/or can skip if too hard * [d] Destructive. Might not be able to go back. == Preparations == * [A] Tune f1, f2, f3 frequencies to IMC FSR. * [B,d] Replace all the in-vac steering mirrors and pick-off mirrors to proper ones [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=12592|JGW-T2112592]] * [C,d] Also POP and POS in-vac and in-air dichroic mirrors if necessary. * In the process of finalizing the specs * [B,d] Replace all the beam splitters in in-air optical tables to non-polarizing beam splitters [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=12956|JGW-D2112956]] * This is necessary to estimate the polarization content of the interferometer correctly (without too much confusion) * BSs arrived at Mozumi on June 30 * [B,d] Install polarization optics to backward POP or POS, and TRY and TRY. * This is necessary to estimate the arm cavity round-trip loss correctly [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=11633|JGW-T2011633]] * Items not yet purchased * [A] Check actuation efficiencies of IMC mirrors, frequency actuation efficiencies of PSL. * [B,d] Install picomotor+PZT steering mirrors for POP green and POS green. * Ordered on June 29 * [B] Install coil driver switch for ETMs (and ITMs?). * High power for lock acquisition, low power for low noise mode. * High power for ETMX and low power for ETMY is also possible, but anyway we need a switch to turn off the driver. * [C,d] Install picomotors to center the beam on oplev QPDs and ASC QPDs. * Already PZT mirrors installed for some ASC QPDs? * [C] Inject a fake RF signal to PDA1 to reproduce the spurious coupling around the REFL table and ALS racks * klogs 10958,10959, 11014, 11315, 12382, 12392, * Perhaps illuminating PDA1 by intensity modulated light maybe interesting. * Insert Baluns as necessary. [[https://dcc.ligo.org/LIGO-E1200148/public|LIGO-E1200148]] * Do other things also. * [C] Check ground issues of RF PDs and RF QPDs. * [B] Assemble optical table covers * IMC REFL: arrived, not assembled * TRX and TRY: ordered * AS: arrived, not assembled == Xarm == * [A] Measure the finesse at room temperature and at cryogenic temperatures, for both 1064 nm and 532 nm. * [B] Measure the round-trip loss by taking into account the effect of birefringence correctly. * Measure the beam spot position dependence. * [A] Measure the amount of POP/POS p-pol when the arm is locked and unlocked. * [A] Measure the mode-matching for both 1064 nm and 532 nm. * [B,d] Tune the Gouy phase separation between two QPDs at REFL/AS/TRX. * Make sure all the signals are in in-phase. * [A] Measure the alignment sensing matrix at REFL/AS/TRX, for ITM and ETM. * Try closing ASC loops. * Check TRX IR QPDs. * [A] Measure modulation depths for f1, f2 and f3. * [A] Check ITM and ETM actuation efficiencies. * [B] Make a power budget of each ISC detection port. * [B] Refining the automation -- mainly for the successive full ifo initial alignment. * [B] Leave a record on the demod phases -- for repeating the Schnup asymmetry measurement. * [B] Establish IR/Green co-alignment procedure -- for full ifo initial alignment. * [B] Could we check out the common mode servo board at this point? * [A] Check new fiber noise cancellation system for ALS. * [B] Goal of ALS: RMS of 1.7 Hz (CARM width) == Yarm == * Same as Xarm. == Michelson == * [A] Check BS actuation efficiency. * [A] Check out the LSC optical gain. Should be easy enough to doublecheck. * [A] Measure, again, the contrast defect. * [C] Measure the mode content of AS beam using OMC. * [B] Record typical Mich length noise. * [B] Close the ASC loops -- mainly for the purpose of the initial alignment automation. * [B] Refine the automation. * [C] Check why the alignment procedure of Xarm->Yarm->PRMI is not good and we took Xarm->PRMI->Yarm. [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=12594|JGW-T2112594]] * Check beam spot positions on mirrors? == Power recycling cavity == * [B] Measure PRY length and PRX length. * Previous methods give inconsistent results and also not compatible with Schnupp asymmetry measurements. * [C,d] Tune IMC length to PRC length (and re-tune sideband frequencies). * [A] Check actuation efficiency of PR mirrors. * [A] Measure PRC Gouy phase. * [A] Close the ASC loops. * [B] Refine the automation. * [A] Check out the power build up in the carrier-locked and side-band locked conditions (PRMI) * [C] Correlation measurement of p/s-pol sloshing (https://klog.icrr.u-tokyo.ac.jp/osl/?r=9333) against angular fluctuations or whatever. * [B] Identification of any drifty suspensions as the carrier is locked -- to support the coming full lock operation. * [B] Tune up the triggers and filter shapes for fast lock acquisition. == Signal recycling cavity == * [A] Check actuation efficiency of SR mirrors. * [A] Measure SRC Gouy phase. * [B] Automation? == Dual Recycled Michelson == * [A] Measure power recycling gains for carrier and sidebands, with and without SRC. * [B] Measure length sensing matrix. * Both for 1f and 3f signals. * Optimize the modulation depths if necessary for sufficient signal-to-noise ratio for 3f signals. * [B] Measure power at each ISC detection port when DRMI is locked. * [B,d] Tune the Gouy phase separation between two QPDs at POP. * [B] Measure the alignment sensing matrix at REFL/POP/AS. * Try closing ASC loops. * Most notably the f1-f2 WFSs at AS (RF QPD is already installed) * [C] Examine the mode-hop criteria (https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=12213) * Which mirror affects most and how much angular motions are tolerable? * Is the SRC Gouy phase large enough? * [B] Refine automation. * [B] Make a noise budget for MICH/PRCL/SRCL. == Fabry-Perot Michelson == * [B] Measure length sensing matrix. * [B] Measure power at each ISC detection port when FPMI is locked. * [B] Measure the alignment sensing matrix at REFL/POP/AS/TRX/TRY. * Try closing ASC loops. * Test out the radiation pressure basis actuation scheme (SOFT/HARD) * [A] Do some noise hunting at low frequencies and VIS commissioning with FPMI * Perhaps interesting to lock OMC to check out the freq/int noise couplings (down to ~10 Hz) to AS port. * Also, rf phase and amp noises. * [B] Measure the contrast defect, compare it with Michelson. * [C] Measure the mode content of AS beam using OMC, compare it with Michelson. * [B] OMC ASC commissioning? * [C] Repeat the same measurements as described in * klogs 10958,10959, 11014, 11315, 12382, 12392, * to make sure whether the problem still persists or not. == Power Recycled Fabry-Perot Michelson == * [B] Measure length sensing matrix. * [B] Measure power recycling gains for carrier and sidebands. * [B] Measure power at each ISC detection port when PRFPMI is locked. * [B] Measure the alignment sensing matrix at REFL/POP/AS/TRX/TRY. * Try closing ASC loops. * [B] Refine automation. * Review/refine the O3GK lock acquisition process. * [B] Measure frequency/intensity noise coupling, down to ~10 Hz. * [B] Measure MICH/PRCL to DARM coupling. == Resonant Sideband Extraction == * [B] Measure length sensing matrix. * [B] Measure power recycling gains for carrier and sidebands. * [B] Measure the cavity pole. * [B] Measure power at each ISC detection port when PRFPMI is locked. * [B] Measure the alignment sensing matrix at REFL/POP/AS/TRX/TRY. * Try closing ASC loops. * [B] Measure MICH/PRCL/SRCL to DARM coupling.