2022/08/05
(1) Suspension health check for PRM/2/3/ BS SRM/2/3 IMMT1/2: (Takahashi-san and Ushiba-kun and selected people)
A01: Cable check:
- Abnormal cabling は使ってないか、あとで、直せる。
A02: Porality Check
- All are identified using a magnet meter. So different with each other (PRM/2/3)
Why the only one "N" is selected in PR2 for the bottom filter? -> maybe a mistake. -> we cannot recover this situation.今後はconceptを統一してください。ばらばらにならないように。
A03: Rubbing Check
- According to inspection by camera etc, at present gaps are enough.
- When the height position is adjusted, the gap can be small.
- concept of earthquake stop:
- Smaller is required to avoid a magnet-drop accident.(IM/TM)
- Some should have larger to avoid accidental touching. (BF)
A04: Range and Calibration (Actuators performance check)
- PR3 case, the range seems to be small.
- we should avoid stuck during the range check. So we avoided in PR3. Please add this information in the page.
- How much are these ranges affected by temperature?
- Heaters are enough to compensate? It is difficult to test in the air.
A05: Watchdog Settings
A06: Height Setting (Mirror Position) -> Beam paths
- Finished yesterday.
- each keystone position was measured.
- What is the conversion factor?
- values are the setpoints. These input values should not change as long as we touch the hardware. calibration can vary.
A08: LVDT Calibration and performance
- value distribution is so large. Why?
- demodulation phase? gain adjustment? Takahashi-san did not make LVDT. He just checked calibration.
- LVDT noise/comparison with ADC noise?
- OSEM
A09: Spectrum
- IN1: counts values.
- Healthy spectrum? How to judge?
- Spectrum with some damping control (aligned state)
- IM/PR2 shows a different spectrum.
- Noise floor for high-frequency range is OK.
- 制御あり無しでとってほしかった。なしのほうもとっているので、あとで、準備。
A10: Transfer Function
- BFD: Bp系はBFV以外はみな同じ感じ。
IML:Bp系はVertical 以外は同じ感じ。Verticalは違う。IMP/Yはかなり個性がある。
- GASはBFのPRM3が共振が大きい？(page 5)
- page9: 比較は難しいのではないか？このプロットで言えるのは、共振周波数などが同じなので、こすってないとかしか言えないのでは。
A11: Traverser performance and safety protection
- According to the work during off-loading in klog, they can be smoothly worked.
- The limit SW test was avoided by moving actual traverser. Limit SW
(2)Oplev Check for PRM/2/3/ BS SRM/2/3, except for inevitably removed poles/optics for vacuum parts setting. (Yokozawa-kun)
Beam Power
- 0.7-0.8 mW input:
Beam Path Clearance
- PRM: has a large gap.
- PR2: checked.
- PR3: Next week's homework.
QPD centering
- Done.
Calibration
- Done.
PYL Separation(after pumping?)
Spectrum Health
Oplev beam's stray light influence
- almost no light.
Covering
- we will do this after closing.
PSD power suppliers will be put in other places. Thermometer set
2022/08/19 and 26
(1) Suspension health check for SRM/2/3 and BS: (Takahashi-san and Ushiba-kun and selected people)
A01: Cable check:
F1 GAS LVDT -> Circuit change. It works.
IM Pico SR2 -> It works again.
- F1 Fishing rod -. recovered.
- BS again on 26th
IM Pico 8-G -> grounded !! it seems to happen during vac work. -> next week's check. ADC problem happened. So if we can solve this, we will do.
A02: Porality Check
- Polarity Confirmed.
A03: Rubbing Check
- SRM: we adjusted a stopper that was very close to the facing object.
- Others seem to be enough. 3mm is enough? We would like to keep the max adjustable range of IP.
- We will try extend the gap in the next week except for BS.
A04: Range and Calibration (Actuators performance check)
- SRM F1 StepperH is quite large. It is OK because the comparison with other suspensions has no meaning.
A05: Watchdog Settings
A06: Height Setting (Mirror Position) -> Beam paths
- OK
A08: LVDT Calibration and performance
A09: Spectrum
- BS GAS LVDT is larger than the others (x4~6). It means the S/N is worse. If it became a problem, we should gain the LVDT driver up
The noise floors of some LVDT channels were larger than the others by about one order. -> recovered by replacing a card.
A10: Transfer Function -> improvements will be done in the next week.
- Please replace the TF data with the newest data. Ushiba-kun shows the HF area performance can be matched with each other.
- The DC magnitude of TM-L TF in SR2 is smaller than the other SRs. The gain of the length Oplev should be checked.
- The DC magnitude of H1 TF in SRM is 5dB smaller than the others. Though we tried to swap the OSEM channel to H2, it was not changed.
- Gap improvements for SR2 to reduce the Q value.
BS outer frame discussions
(2)Oplev Check for PRM/2/3/ BS SRM/2/3, except for inevitably removed poles/optics for vacuum parts setting. (Yokozawa-kun)
Beam Power
Beam Path Clearance
QPD centering
Calibration
PYL Separation(after pumping?)
Spectrum Health
Oplev beam's stray light influence
Covering
PSD power supplier wll be put on other places. Thermometer set
SR area inside photo and Oplev beam position photo
(3)Mid-size Baffles (Akutsu-kun and his selected persons)
Done on 22nd August.
Approved all processes of setting the mid-size baffles.
(SR3 oplev path is pointed out to be near the structure.)
(4)Beam Path (Ushiba-kun, Tanaka-kun?, Hirose-san?)
Main beam - IR beam hit and through around the center (or acceptable area) of optics from inside IFI tank -> SRM.
GR beam - GR beam hit and through around the center (or acceptable area) of optics?
- (assuming GR beam on POP/POS also pass through around the center (or acceptable area) of optics)
IR from the misaligned PRM - Does it hit on the Dumper? - The misaligned position repeatability is good or well controlled by oplev/something?
Relative positions btw Mid-size baffles and IR/GR.
AR-SRM reflection beam control - Where is the reflected beam from SRM? When misaligned, should it hit the mid-size baffle on SR2 or other? Should we make it possible to align SRM even if it has less reflectivity for RSE?
(5)IFI-IMMT tank
Stray light mitigation(Akutus-kun and selected persons) - The predicted stray beams are dumped? - Is there any missing stray beam paths?
ISS beam/CWP reflection beam extracting (??) - the beam paths are clear? - The beams hit around the center of windows? - The reflected beams on the windows are dumped?
(The IFI new poles seem to be dangerous due to the vibration made by drilling.)
Beam dumper(Akutsu-kun and selected pesrons) - Does the thermometer works?
(6)Vacuum system (Kimura-san / Uchiyama-kun and their selected persons)
Numbering for all ports.
Check the flange seal surface condition.
Decide where the elastomer/Metal gasket will be used.
Top hat seal surface check for SRM/2/3 BS PRM/2/3.
ICF152 flange preparation for the new reducer flanges at SRM/PRM.
Check dust/fungus in stocked tubes/bellows.
(7)Cleanness of Mirrors HR/AR
FC was done for all mirrors' HR/AR, except for OMC Typ-C mirrors.
Check the surfaces and inside again before closing, and blow/absorb as much as possible if you find anything.
(8)Vacuum tank cleaning
In Basic, the cleaning was done after FC. Check inside again and clean just before closing if you find something.
(9) MICH performance
Can we obtain MICH fringe with the aligned ITMX/Y and BS at the REFL PD? Should we lock MICH using REFL PD?
(10)misc
Put Si plate for the dust monitoring? (Si plates/holders were bought well before.)
Mirror View Camera Should we recognize the view image under the bright condition? (Which parts can be seen where in the image.)
Are there any leaning materials on the suspension support frame!?
Are there any stressful cablings on flanges?
2022/08/22
Mid-size Baffle
All mid-size baffle settings were assured to be set properly.
2022/09/16
IFI/IMMT/PRM Closing
- Stray light dumping
- Main optical path through IFI, CWP, and on IMMT1/2, ST1/2 (including replacement and height adjustment)
- IFI height adjustment
- Reflection beam from PRM and its dumper
- Beam for ISS
- Beam for IMMT1 trans
- CWP reflection beam
- Scattered light guard plate
- Stray light dumping
( * confirmation of all optical paths.)
- PRM health check and operation (Takahashi and ??)
- Health check(done before)
- Operation for misalignment
- IMMT1/2 health check (Ushiba)
- TF
- Gap between magnets and facing plate.
- Actuator efficiency and healthy movement
- Cable Connection for each item. (Each person)
- How to close this area. (Uchiyama)
- MCF-IFI
- IFI-IMMT with the optical path check