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Reports until 09:11, Thursday 24 May 2012
H2 AOS
thomas.vo@LIGO.ORG - posted 09:11, Thursday 24 May 2012 (2937)
ITMY Optical Lever Alignment
Gerardo and I are attempting to align the optical lever, we are able to hit the ITM relatively easily but on the reflection back to the QPD, we get this terrible scattered pattern shown in the pictures attached.  We thought it might be the telescope so we switched it out and it just gives us a different scattered pattern with fringes.  It is clear that there are multiple reflections and fringes but we tried hitting all parts of the ITM to make sure we're not clipping somewhere and it doesn't change the pattern.  We also looked at the beam coming out of the telescope and it looks very circular and focuses down well, approximately 25 meters away the spot size looks about 2 or 3 mm in diameter.  So I'm confused, I'm thinking maybe during installation and de-installation the telescopes got bumped and need to be refocused(which I've never done before), or we're using the wrong ones all together.  Another weak point would be the fiber optic cable getting crimped, but there's a  possibility that we're hitting something inside the chamber is messing up our reflected beam (the pattern looks very similar to Van Gogh's Starry Night).  Investigating causes now.
Images attached to this report
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