A rough consistency check of the actuation strengths with the FSM + MICH measurements, using a method developed by W. Ogaki (a previoius such measurement can be found in klog 11754).

Below we provide our preliminary results.

From FSM,

• the MICH optical gain was estimated to be 1.826e+11 ct/m

Then, with MICH locked, the following quantities were aquired:

• A_BSTM gain: 5.457e-12 m/ct
• ratio of A_IXTM / A_BSTM gains: 0.09186
• ratio of A_IYTM / A_BSTM gains: 0.1037
• ratio of A_EXTM / A_IXTM gains: 0.8623
• ratio of A_EYTM / A_IYTM gains: 0.5912

From this we can estimate A_ETMX and A_ETMY actuator strengths:

• at 1 Hz, A_EXTM = 4.322e-12 m/ct
• at 1 Hz, A_EYTM = 3.346e-12 m/ct

The MICH result for A_EXTM is within 17% of the DARM result. And for A_EYTM, within 6%.

We have not analyzed the uncertainties associated with MICH results yet.

Each of the estimated values are weighted averages taken from TF measurements (weights were set using coherences associated with the measurements).