Somehow the angular stability of the central part have not been so great.
Also the angular motions look fluctuating a lot and they seem to be related with the glitches.
I took the oplev spectra when the PRMI is locked and unlocked to see whether if something obviously crazy is going on or not.
They seem ok to me except that the PRM pitch shows an extra bump at around 2-3 Hz when the PRMI is locked. But I don't think it's prominent.
- The attached files show the oplev spectra. When the PRMI is locked the PRM and both ITMs are under the length control.
(red) pitch when PRMI is locked
(blue) yaw when PRMI is locked
(orange) pitch without any length controls
(cyan) pitch without any length controls
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