With Hirata-san and Ikeda-san.

See pictures in the album BS Remedying work after O3.

We added some weight by replacing some ballast masses:

• Removed:
  • 4 × 10 mm × 30° ( = 4.387 kg)
  • 3 × 3 mm × 60° ( = 651 + 651 + 602) g
  • 4 × 3 mm × 120° ( = 5.6 kg, 1.4 kg each)
• Added:
  • 2 × 20 mm × 120° ( = 16.6 kg , 8.3 kg each)
• The overall change was an addition of 4.71 kg
• The temperature was T = 23.8 °C

In  the transfer functions the resonant frequencies are 63 and (around) 92 mHz, measured with a resolution of 5 mHz. As before, L and T look strongly coupled.