Agenda/Minutes

CRY+VIS Interface Meeting

Date: 2022/1/14 13:00-13:30

Participants: Takahashi, Yokozawa, Ikeda, Ushiba, Aso, Uchiyama, Sato, Hirata

IX: Health check. Spectrum was improved. Investigation of the glitch in the F3 signals is still ongoing. Windshield for the MN oplev is not working well.
EX: Health check.
IY:
EY: ALIGN mode is available. LT->Yaw coupling is large. Preparation for ACCs.

Replacement of flip cables: SRM has not been finished yet. Cables for Type-C will be delivered in the end of Jan.
TM height setting: ITMY.
Oplev: Setup of the TM Oplev in IY after the TM alignment.
ACC: Preparation for EY.
Commissioning in air: Return of GRY. Alignment of SR3/ETMY.
Commissioning in vacuum: Go to the stable lock.
Overall commissioning:
Acceptance check:
PF actuator: At the in-vacuum commissioning.
New vacuum pumps for V-chambers: Cabling of the power line in IXV/EXC on 1/11-12.
Heater control: Test in IXV/EXV is planed. Repaired power controller will be delivered on 1/17.
Power source for Oplev:
Tunnel for the IYC booth: Planned on 1/31.

Date: 2022/1/14 14:00-

Participants:

Preparing for the ACCs in EY. The tuning of the resonant frequency was finished.
Fixed the cables around the IP in EY.
[Terrence] We aligned the EY and get the reflected green under the following condition:
- IP L, T, controlled.
- BF Y, controlled.
- Coarse alignment of yaw using BF yaw pico motor.
- Coarse alignment of pitch using MN pitch actuation.
There's something strange. I can't engage all IP controls at the same time. It used to be okay. I will check them later.

Terrence reported SR3 wasn't healthy, the TF measurements looked bad.
We inspected the suspension and found several security structure screws touching the IM or IRM.
This suspension was healthy, how did it become unhealthy?
- As they should be, the screws were likley close to the IM and IRM and began touching the payload when yaw was adjusted with the F0 stepper motor.
- When we removed the F0 yaw stepper motor we followed a method to keep the same yaw position, but it seems it was not accurate enough.
- We lost the alignment give by the oplev.
- The incident angle of the green beam might have changed also.
Terrence updated several control filters of the SR3 and modified guardian.
- In the beginning, I thought the yaw oscillation was due to misbehaving control loops at the IP so I modified them in the beginning but turned out it was not helping.
- I modified the rest of the control filters for consistency.

They inspected the PR3 traverser to check whether it had the locking assenmblies or they had been removed.
We calibrated PRM SF LVDT. The calibration factor hasn't been written in the medm screen yet.
In PR2, we connected the cable for TM-H4. A cable with the same label has beed connected. There are old cables around that flange and they should be removed.

(Date in Kamioka)

The week from 1/17

The week from 1/24

KAGRA/Subgroups/VIS/VISMinutes20220114 (last edited 2022-01-14 14:31:56 by RyutaroTakahashi)

-  ⇤ ← Revision 10 as of 2022-01-14 13:59:04 → 
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  Editor: terrence.tsang
  Comment:
+   ← Revision 11 as of 2022-01-14 14:00:41 → ⇥
  Size: 3923
  Editor: terrence.tsang
  Comment:
-Deletions are marked like this.
+Additions are marked like this.
 Line 63:
-  * In the beginning, I thought the yaw oscillation was due to misbehaving control loops at the IP so I modified them in the beginning but turned out it was.
+  * In the beginning, I thought the yaw oscillation was due to misbehaving control loops at the IP so I modified them in the beginning but turned out it was not helping.