sebastien.biscans@LIGO.ORG - posted 11:00, Thursday 21 November 2013 - last comment - 14:49, Thursday 21 November 2013(8666)
ISI-ITMX rubbing
Find attached the plots of last night transfer functions.
As you can see, something bad happened at the resonances around 1Hz since we put the dome on. This badness appears on the vertical sensors, both stages. It mostly seems like a rubbing cable.
Hugh and I are going in the chamber right now to see if we can find something.
PS: L4C-H2 presents a gain of 0.5. We'll fix that later.
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Recall - as I pointed out below, when we go the "handoff" from SEI to close the dome and move on with other chamber closeout items, I clamped the ITMx optics.
Thanks for the recall Betsy. I think we found our issue here! I'm running quick measurements right now to double check, but we should be good to move on soon.