[R.Sato, Washimi]

We analyzed the swept sine shaker injection test for the IFI chamber's bellows leg performed on Feb. 11 (klog32636).

Even though the excited lines in the seismometer signal were narrow, the excess in the strain signal got wider around the injected frequencies.

Moreover, the strain signals around 60 Hz were also excited when the shaker oscillated around 120 Hz.

These results mean the couplings from the ground vibration to the strain are non-linear and transfer functions are inappropriate for estimating the noise budget.