Minute of KAGRA commissioning meeting

• Date: 2018/6/19 11AM~12PM
• Attendance: Miyakawa, Aso, Yokozawa, Ohishi, Kokeyama, Miyoki, Tahara, Enomoto, Stefan, Tomura, Ushiyama, Nakano
  • eZuce: Ushiba, Izumi, Inoue, Yamamoto(Toyama), Suzuki, Hirose, Shoda

0. Schedule

• k1ix0 will be needed by September for NAB PD.

Laser

• Transmissivity of Faraday Isolator suddenly reduced 60% to 40%.
• Starding Fiber amp failed due to too low power at the sensor.
• We will use spare at Mio labs. We can use current low power laser, so schedule won't be changed so much.

IMMT

• http://klog.icrr.u-tokyo.ac.jp/osl/?r=5274

• http://klog.icrr.u-tokyo.ac.jp/osl/?r=5287

• http://klog.icrr.u-tokyo.ac.jp/osl/?r=5292

• Changed titanium screws.
• IMMT1 repare was done, with 1cm position accuracy.
  • 1cm is not enough(Izumi).
• IMMT2 repare will be held 7/9~.

PMC

• http://klog.icrr.u-tokyo.ac.jp/osl/?r=5295

• Offset was implemented.
• Whitening will be implemented by daughter board.
  • Needs gain at low frequency in digital loop.

Useful scripts for RT-models

• http://klog.icrr.u-tokyo.ac.jp/osl/?r=5282

• http://klog.icrr.u-tokyo.ac.jp/osl/?r=5224

  • ring on f0 got lower and on the f1 by a few mm.
  • f0 TF had no response. Line to coil was cut. It had been repaired before and it was used again.
  • It will be fixed around September as 1week work. Whole coil will be replaced.

X arm commissioning/preparation

• WFS target: 10nrad.

Satellite box modification

• https://gwdoc.icrr.u-tokyo.ac.jp/DocDB/0083/G1808352/001/G1808352_v1.pdf

• 100nF cap will be implemented to avoid an oscillation. It introduce 41Hz pole.

MC realignment

• MC will be re-aligned today.

FSS BO

• BO card was broken and it was replaced.
• BO check card is still connected between BO card and circuit to break ground loop.

PMC installation, circuits, adding offset

• http://klog.icrr.u-tokyo.ac.jp/osl/?r=5227

• Trying to implement an offset using slow output into EXC.

Others

• Next meeting: 6/19.