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• VISMinutes20190816

Agenda/Minutes of the VIS Meeting on 2019/8/16

2019/8/16 14:00 - 15:30

Zoom Meeting

Participants: Takahashi, Fabian, Aso, Tanaka, Ishizaki, Lucia, Fujii, Miyo, Shoda

Progress report

Type-A

Past week report

• For the 150mHz-ish mode damping
  • sensor correction for IP, i.e., seismic signal subtraction system, was implemented to all the type-A suspensions.
  • BF-L/T damping was also implemented for this damping.

    • The RMS was suppressed by a factor of like 2.7, log 9961

  • (SC at IP) + (BF-L/T) made the system quieter compared to the previous, however, it was not enough
    • IP-TF does not have the peak at 150mHz-ish.
    • BF-actuation efficiency is not so high.

    • => we will try to the feedback like BFl to IPL, or TML to IPL, for the next.

      • For this purpose, we have to modify the model again.

• For inertial damping performance test, LVDT damping vs. inertial damping > By Lucia

  • ETMY: 9981

  • ITMX: 9995

    • What is the summary for this week?
• length-oplev calibration with green lock

  • log: 9989

  • 1st trial. The values are *NOT* installed to the MEDM since we could not guarantee if we were observing TML motion not TMY motion. It looks they are not terrible values, compared to ground motion though.
• F3-GAS of EY: looks stacked again

  • log at 2019 Aug. 15th, when it was stuck: 9990

  • log at 2019 Aug. 15th, when it was free: 9293

    • The difference between the above is like about 405um (it went to lower position), based on GAS_LVDTINF_OUT channel.
• ETMY health check

  • lopg: 9996 => status and plan?

• Listed up the modification parts in the 3D CAD model.

Plan for coming weeks

• Guardian stuff
  • utilize the TMY to BFY loop again, etc.
• RTmodel modification
  • make paths from TM to IPL, BFL to IPL.
• 150mHz-ish suppression
  • implement loops like TM to IP.

Type B

Report for the week 15-08-2019

• Shoda-san improved the SR3 optic yaw motion (klog 9949).

  • Improvement in the frequency band from 1 Hz to 2.3 Hz was achieved by modifying the IM-Y filter. The problem was not enough phase margin.
  • There's still a peak at 1.3 Hz.
  • She also modified the IM SENSALIGN matrix (diagonalization according to resonance peaks?)
  • Transfer functions should be measured again.

• The BS optic has a large peak at 150 mHz (klog 9991).

Plan for the week 19-08-2019

• Enomoto-kun requested to extend the oplev control loop down to where the micro-seismic peak is. (Fabian.)
• Assemsment of the motion of the SR optics around the micro-seimic region. (Due today.)

Type-Bp

Past week report

Plan for coming weeks

OMMT & OSTM (Takahashi)

Past week report

• Ordered the dummy mirror to be used for gluing test.

Plan for coming weeks

VIS electronics

Past week report

Plan for coming weeks

Other site works

Safety

• Incidents:

Discussion

• For the people in Kamioka, checking the presence/absence at the site will help us (not only for Mitaka persons).

Travel Plans

• Travel (Week of 8/19):
  • Takahashi: 22-24(F2F)
  • Sato:　
  • Hirata:
  • Shoda:
  • Fujii: 19-24
  • Tanaka:
  • Fabian: 22-24(F2F)
• Travel (Week of 8/26):
  • Takahashi:
  • Sato:
  • Hirata:
  • Shoda:
  • Fujii: 26-30
  • Tanaka: 26-30

Next meeting

On 2019/8/30(Fri)