Commissioning Strategy Meeting for O4a (2023/3/24)

• Zoom3: https://zoom.us/j/5045179604

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Commissioning Term

• O4a: starting at 24 May, ending at the end of June?
• Remaining commissioning term: 2months until O4a, including;
  • Golden Week holidays(3-7 May)
  • GWADW2023 (21-27 May)

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• Can we work in KAGRA from am 5:00 ?? -> Consult with Ohashi-san

• How much late is allowed in the night?? -> It is allowed until 9PM with permissions. In the case of no permissions, being consulted with Ohashi-san

• Discussed with Ohashi-san. Safety management is the issue.

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On going noise hunting

• We need a noise budget curve.
• ( ) shows the term which each item needs
• Stable operation is

Short term

• MICH control noise around 30-100Hz. (1 week) -> 3/9~ on going, expecting ~2 times improvement 30-100Hz on DARM.

  • Dark noise limited. -> needs more input power. POP light is now very weak.

  • RELF can be used for MICH signal-> Needs 17MHz RFPD. -> Needs simulation before replacing RFPD.

• CARM noise above 100Hz~. (1-2 weeks) -> 3/9~ just started. Next most important item.

  • Floor can be limited by CARM.

  • Projection results showed always overestimated plots.

  • Not only residual noise, but also DARM seems to be affected in other path. -> may need more input power.

  • Changing CARM gain affected only above 300Hz~.

• ISS

  • ISS has sometimes breath noises. -> to be checked and fixed in 3/20 week.

• Some bumps in 100-1000Hz (unestimated)
  • Any other items to be turned off?
    • Turbo pumps on somes are center and EXV EYV.
    • Air compressors.
  • Injection test on;
    • IFI legs separately

      • Needs TF of stacks -> Takahashi-san will upload.

    • Remaining OMC chamber legs
    • OMC chamber (not legs)
    • PSL room
    • BS area and ITM area
    • End station

Middle or long term

• ASC (several weeks)

  • Some ASC should be on to stabilize OMC.

    • Hirose-san's result showed that birefringence makes almost no affect on slope of error signal and offset on error signal.

    • WFS for ETM common was engaged by REFL with some offset.

      • WFS for ETM diff needs to be engaged.

      • ITM common, diff needs to be engaged? or is ADS enough? -> ITM should be tried.

      • Increasing WFS BW may cause a noise at high frequency.
• Shot noise above 1kHz (several weeks)

  • Almost comparable to CARM above 1kHz. -> needs more input power.

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Extra noise hunting

• Shotnoise

  • Laser power from 1 to 5W (several weeks)

  • Laser power from 5 to 10W (month?)

    • Laser power increase strategy -> Arm cavity instability mainly of Pitch.

      • Oplev in Marionet has been installed, it may help.
    • Many measures were prepared. So this pitch can be suppressed. Not so serious.
  • Laser power more than 10W (several months?)
• PRCL

  • noise budgeting is important.-> We will update PRCL noise budegt curve after feed forward.

• Suspension control around <100Hz for some suspensions

  • local control optimization(filter correction) to reduce the contrast fluctuation? -> Ushiba + alpha

• Suspension control around the micro-seismic area
  • try the bottom filter dumper sensor correction in L
  • Terrence method trial in future
  • can improve residual seismic noise.
• PEM/DetChar activities

  • Summary of the recent PEM n oise hunting on 2023-03-10 JGW-G2314870

  • Summary of the recent PEM n oise hunting on 2023-03-10 JGW-G2314870

  • Oplev for IMC may help.
  • Effect of increasing water will be investigated.
  • Ground motion investigation needed.
  • Bruco shows sometimes has coherence ALS to DARM for example, so please keep watching Bruco.
  • Noise hunting with Hveto could be useful.

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Controls

ASC

Laser

• Switching from current fiber laser to NEOLase HPL. -> After noise-hunting.

  • What is the milestone to change HPL
    • 1Mpc ?
  • PLL adjustment is bothering us!!
• ISS
  • below 3Mpc line.
  • Automatic gain adjustment depending laser power should be implemented.
  • ISS alignment control should be implemented.

Vacuum

Coolling

• Cryocooler effects is serious or not? According to Yamada-kun's thesis, no effect for the designed sensitivity.
  • We can check by just operating motors.
  • We get peak noises and enhanced noises for the frequency range of 10~100Hz.
  • Seismic noise comparison?
  • We will measure sensitivity curve with stoping 4 cryocoolers for the duct cooling of IXC and IYC next week for the short time as like 5 min.
• 3 mirrors(IX, IY, EY) cooling(~2 months(assuming "1 month for one mirror" and "one cooling in one arm at the same time".)
  • How much commissioning time will be used for
    • suspension height adjustment
    • drifting
    • PY/L coupling adjustment

    • resonance mitigation control in -> minor adjustment is enough, mainly in gain.

• What is the milestone -> Please decide who set the milestone. Miyoki-san.

  • 1Mpc?
  • If we open the chamber, we should hesitate to cool down mirrors.

• Can we cool during O4?-> No discussion.

Maintenance for the long operation

• SRM vacuum sensor problem. -> A spare is ready. Replacement will take long time. One day is necessary.

• Cryo-coolers
  • We need maintenance after O4.
  • High purity helium gas is neccessary for the maintenance. preparation has already started.
• Electric ground

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Done or Non related topics

• We need a noise budget curve for discussion about the strategy. Please announce that without observation range, we can upload a sensitivity curve in the Klog.->Comissioning leader (Miyakawa-kun)

• Daily commissioning strategy is necessary!
  • More precise time sharing and assignments are necessary.

  • Can we work in KAGRA from am 5:00 ?? -> Consult with Ohashi-san

  • How much late is allowed in the night?? -> Consult with Ohashi-san

  • Discussed with Ohashi-san. Safety management is the issue.

Short term

• Noise injection around IFI chamber. (1 week) -> 3/3~3/7, ~2 times improved in BNR!

• MICH control noise around 30-100Hz. (1 week) -> 3/9~ on going, expecting ~2 times improvement 30-100Hz on DARM.

Noise hunting detail

• MICH

  • noise budgeting is important. -> We will update MICH noise budegt curve after feed forward. --> <<Priority 1!!>>

  • Sweptsine measurement is better.
  • Gain tuning? Not so much, Almost Constant.
• Seismic noise isolation of OMC?? (~ 6 months??)
  • where is the noise due to the "normally expected" seismic noise?
  • Some selection

    • no opening vacuum tanks <- low seismic noise environment to realize 1-3Mpc

    • opening vacuum tanks <- if scattered light ? new injection path is also possible.

  • TMPs were off on OMC/SRM at present.-> Done

  • Seismic noise is still larger than O3GK now.

  • Can we reach the O3GK sensitivity level if we can realize the low seismic noise level? -> Washimi-kun -> We can reduce or not

  • According to Washimi-san's evaluation, even though we achieve low seismic noise like O3GK, 1Mpc observation range is difficult. We need more.

    • Results of evaluations

    • Action list to realize low seismic noise.

  • We shall do the tasks in the list to obtain better sensitivity. Then we will do injection test and hummring test. Finally, we will decide whether we open OMC to install the beam dump or not.
  • If we open OMC, what should we check?
    • scattered light on the cable? that was identified by Akutsu-kun.

    • Design of beam dump

    • Blade spring resonance? No data.
    • Up conversion noise implies scattered light noise?

      • OSTM swing to check the scattered lights? -> Ushiba->Swing test has been done. No excess noise found.

      • Slow actuation of suspension -> PEM team -> No chance this week.

      • Hummering/acoustic test? ->After sensitivity improvement.

• There are stable noises in the current sensitivity such as ADC noise and so on. We need a noise budget curve for discusion about it.
• PEM/DetChar activities

  • IMC injection test <<Priority !!>>

  • https://klog.icrr.u-tokyo.ac.jp/osl/?r=24247 <<Priority !!>> -> Some strategies.

• Whitening filter apply
  • Main channel application seemed to be OK.
  • For IMC(Oplev, QPD, ...) it will be applied.
    • Frequency band? What is the strategy?

    • Any evidence ADC noise is dominating the present QPD. -> Calculation is necessary -> Evidence is obtained? Dark noise?

• REFL power up

  • 10 times larger than before now, still smaller than O3GK case. <- Contrast fluctuation problem affects.

    • Power-up timing is important.
    • CARM control noise is where.

      • Even the boost was applied, the expected reduction cannot be obtained in DARM. -> Ushoiba-kuns klog.

• Vacuum stuff

  • Ion pump operation estimation -> Who (Kimura, next week) -> Next week schedule.

  • -> do as soon as possible.

  • TakahashiR-san maybe. + Takahashi-san, Yasui-san
  • Operated Ion pumps: MCE-MCF, IFI-IMMT, PR2-PR3, BS-GVbsy, BS-GVbsx, SR3-SRM, OMMT-OMC. Total 7.
  • Stopped TMPs: MCF-MCE, PR3-PRM, PR2-PR3, BS-PR2, BS-GVbsy, BS-GVbsx,BS-SR2, SR3-SRM, OMMT-OMC. Total 9.

  • changes of sensitivity

  • changes of oplevs

  • Air conditioning Coolers/heaters -. Miyoki

  • SR-C was stooped

• Seasonal water drainage
  • Yarm pumping mid March - mid May

  • amount of water in Yarm is increasing

• MISC

  • Remove unnecessary stuff from the isolated area, especially around OMC. -> Miyoki -> Hayakawa-san is working.

  • OMC: some cabling should be reset. -> Miyoki -> Please check by Aso-san next week.

  • Environment cleaning. -> Miyoki

Laser

• HPL in Toyama U (new 60W characterization -> KAGRA, Repair of 120W from KAGRA)

Controls

• Enhance OMC lock-acquire stability?

  • more guardian improvement(Ushiba, Aso)->Improve has been done. No further problem at present.

  • More dynamic range of PNC-X? -> we have enough stuffs to make more mirror mounts with PZT.

    • Realignment of GR-XY after changing the temp in tne corner station. -> Ushiba, Miyoki.

ASC

• ADS/ASC/WFS for arms to mitigate the contrast fluctuation -> Ushiba->Next week with Aso-san.

  • mysterious off set problems
  • under investigation.
  • Check the TMSX to kill scattered light.

  • ETMY covering -> check effect

  • ADS in FPMI

Suspensions

• no problem in IMC controls

• we need a summary!!(http://172.16.34.76/past_data_viewer/fig_nb/2023/0215/noise_budget_2023-02-15_12:05:26.png)

  • upload this link in JGWdoc/Dac wiki? -> Yuzurihara-kun