I would like to show the spectrum and coherence for interesting channels detected by Bruco

I evaluated each PEM projection for many PEM channels around REFL table.

From these results, vibration of IMC-REFL table looks to be most serious.

(1) Microphone in PRM booth (out side of the REFL box)

(2) Microphone in REFL box

(3) Accelerometer (Z-direction) on REFL table

(4) Accelerometer (Y-direction) on REFL table

(5) Accelerometer (Z-direction) on REFL table periscope

(6) Microphone in IMC-REFL box

(7) Accelerometer (Z-direction) on IMC-REFL table

I also analized the PEM injection data with QPDs instead of PEM channels.

From these results, IMC and IMMT may be weak points.  

MCF

IMMT1

IMMT2

PRM

PR3

Sorry, I had a mistake; SRM -> PRM

In these results, I didn't take the 'intermediate channel effect' into account.

It means this analysis assumes 100% of he QPD signal is  acoustic noise.

I should evaluate the acoustic component in each QPDs channels