[Yuta, Jenne]
In an effort to see what is going on with the beam spot motion, and to investigate whether or not it might be caused by passive TT motion, Yuta and I installed some oplev mirrors in-vac, to make a PR2 oplev.
Yuta did not move either of the in-vac oplev mirrors that are for ITMX. Instead, he took the incident red beam as it was, and put a spare in-vac oplev mirror there. Then he used another spare oplev mirror to get the beam out, and on to the one out-of-vac steering mirror before the QPD. I then steered the out of vac mirror to center the beam on the QPD.
This means (1) that ITMX cannot have an oplev right now, although the HeNe was off anyway, and (2) that as soon as we take these spare oplev mirrors out, we should immediately have ITMX oplev back (may need to steer out of vac mirror to get beam onto QPD).
Yuta is currently taking measurements to see if PR2 motion has high coherence with the intracavity motion. |