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Entry  Tue May 20 16:48:52 2014, ericq, Update, LSC, 3f Stability 3fs.pdfCARMsweepPrcFields.pdf
    Reply  Tue May 20 22:42:28 2014, ericq, Update, LSC, 3f Stability PRCangles.pdf
       Reply  Wed May 21 00:18:40 2014, Jenne, Update, LSC, PRMI locked with REFL33 vs. REFL165 PRMI_outofloop_20May2014.pdf
Message ID: 9976     Entry time: Tue May 20 16:48:52 2014     Reply to this: 9977
Author: ericq 
Type: Update 
Category: LSC 
Subject: 3f Stability 

So, I really should have done this as soon as Manasa measured the arm lengths... I've updated my MIST model with the real arm lengths, but still am using assumed identical losses of 75ppm on each mirror. (I've tried measuring the arm losses for real, but got numbers in the hundreds of ppms, so I need to reexamine things...) 

Here's a simulation of the fields in a perfectly locked PRC when CARM is swept (Normalized to input power = 1). 

CARMsweepPrcFields.pdf

More importantly, here's the latest simulation of MICH vs. PRCL demodulation angle separation in the 3F signals. It seems that we may be getting burned by using REFL33 for the PRC lock. REFL165, on the other hand looks much more robust. We should try this out. 

3fs.pdf

(Some of my previous simulations incorrectly implemented MICH excitations; I only moved the ITMS, not the ETMS along with them, so some other stuff slipped in... )

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