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Entry  Wed Jan 8 13:01:48 2014, Gabriele, Summary, LSC, Effect of PRC length mismatch on error signals REFL_vs_PRClength.pdf
    Reply  Wed Jan 8 16:08:52 2014, ericq, Summary, LSC, Effect of PRC length mismatch on error signals phaseVlength.pdf
       Reply  Wed Jan 8 19:05:30 2014, Gabriele, Summary, LSC, Effect of PRC length mismatch on error signals as11.pngas55.png
          Reply  Thu Jan 9 17:58:31 2014, ericq, Summary, LSC, Effect of PRC length mismatch on error signals 
             Reply  Fri Jan 10 15:31:07 2014, rana, Summary, LSC, Effect of PRC length mismatch on error signals 
                Reply  Sun Jan 12 09:57:24 2014, Gabriele, Summary, LSC, Effect of PRC length mismatch on error signals 
Message ID: 9537     Entry time: Wed Jan 8 13:01:48 2014     Reply to this: 9539
Author: Gabriele 
Type: Summary 
Category: LSC 
Subject: Effect of PRC length mismatch on error signals 

I ran a simulation of a double cavity with a PRC length mismatched w.r.t. the modulation frequency. I summarized the results in the attached PDF. I think it would be important to have a cross check of the results.

In brief:

A mismatch between PRC length and modulation frequency do have an effect on error signals

Multiple zeros appear in REFL_3f/PRCL that can be removed by careful tuning of the demodulation phase (however, the shape of the signal makes difficult to understand which phase is good…)

No visible effect on REFL_1f/CARM

But a large PRCL signal appears in REFL_1f_I, which is used to control CARM. This is not good.

A mismatch of the order of 0.5 cm has a small effect.

 

 

 

 

 

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