Commissioning Strategy Meeting for O4a (2023/3/10)

Commissioning Term

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

On going noise hunting

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

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.
CARM noise above 100Hz~. (1-2 weeks) -> 3/9~ just started. Next most important item.
Some bumps in 100-1000Hz (unestimated)
- Any other items to be turned off?
  - Turbo pumps.
- Injection test on;
  - OMC chamber
  - ??
Shot noise above 1kHz (several weeks)
- Almost comparable to CALM above 1kHz.
- need to increase laser power until ~5W.
- Some ASC should be on.

Middle or long term

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.
  - Many measures were prepared. So this pitch can be suppressed. Not so serious.
- Laser power more than 10W (several months?)
ASC (several weeks)
Suspension control noise (month)

Extra noise hunting

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

Controls

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

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. However, bad alignment will produce a line noise.

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

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.

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

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.