K. Okutomi, T. Yamada, Y. Fujii,


= ITMX / ETMX / ITMY / ETMY =

• We measured the mechanical transfer functions of the payloads:
  • We first cented the following tilt/length-Oplev-spots.
    • ETMX-{MN, L}, ETMY-{MN, L}.
    • Now only IMX-length oplev is *NOT* centered.
      • This is to be installed in the next week with CRYO team.
  • During the measurements, controls of the following tower part were closed.
    • IP-L/T/Y, GASs, BF-Y
    • All of payload loops were opened.
  • Excitation points were:
    • TM-L/P/Y
    • MN-P/Y
  • White noise was injected from 0 to 30 Hz.
  • The measurement files are stored in the following dir:
    •  /users/VISsvn/TypeApayload/${suspesion}/TF/Measurements/20190529/
  • The other settings are snap-shotted in the above dir.
  • The order is as follows, 20 figures (+1) in total:
    • ITMX-{TM-L/P/Y, MN-P/Y}, ETMX-{TM-L/P/Y, MN-P/Y}, ITMY-{TM-L/P/Y, MN-P/Y}, ETMY-{TM-L/P/Y, MN-P/Y}.
  • The suspension models in the filter is to be updated.
    • Of couse, some deteils will be changed due to the coil-balancing work or etc soon though, such information would be helpful.

• According to the results, basically the measurement followed the simulation. However, the TF of *ITMY-P(, Y)* looked a bit strange, as shown in Fig 12, Fig 14, Fig 21 and so on.
  • The issue of the ITMY is to be investigated.
  • The comparison plots (measurement vs. simulation) are also to be added.