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Entry  Wed Dec 18 17:28:50 2013, Gabriele, Summary, LSC, Estimate of the PRC length error data_fit2.pngdata_kick.pngpop110_vs_dL.pngpop110_vs_dL.png
    Reply  Thu Dec 19 12:51:57 2013, Jenne, Summary, LSC, Estimate of the sign of the PRC length error DesignLength.pngPlus5cm.pngMinus5cm.png
       Reply  Thu Dec 19 18:33:25 2013, Gabriele, Summary, LSC, Estimate of the sign of the PRC length error 
Message ID: 9495     Entry time: Thu Dec 19 18:33:25 2013     In reply to: 9493
Author: Gabriele 
Type: Summary 
Category: LSC 
Subject: Estimate of the sign of the PRC length error 

Maybe I'm getting confused, but I still believe there is no way to decide the direction from yesterday's measurement.

Let's say for example that the arm sideband detuning from antiresonance is equivalent to a PRC length change of +1cm away from the position of ideal resonance of the sidebands without arms. Then we can get a measured separation of the sidebands, without arms, corresponding to 5cm both if the PRC is off by +4cm or by -6cm...

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