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 JGW-E2112729
Commissioning (IOO): Evaluation meeting JGW-G2112491
MIF Schedule Estimate for bKAGRA Phase 2 JGW-T1707079
Definitions for the X arm commissioning JGW-T1808343
Definitions for the DRMI commissioning 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 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 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 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. 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. 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.