It is quite likely that we touched the Faraday in Nov 2010.
In this entry http://nodus.ligo.caltech.edu:8080/40m/3874 I wrote that I removed the MCT optics in the chamber.
This is the pickoff between the IMC and the Faraday. This causes the beam shift. Therefore, the Faraday had
to be moved.
There were intensive in-chamber activities from Nov to Dec 2010. I am sure that almost everytime we went into
the chamber, we checked the spot position on the MMT mirrors as well as the TT and PZT mirrors.
Does the miscentering of the spots on the MMT mirrors cause the mode matching significantly changed? |