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Entry  Thu Jun 17 17:09:44 2010, Alberto, Update, LSC, Short Cavity Length Adjustments 
    Reply  Fri Jun 18 13:47:20 2010, Koji, Update, LSC, Short Cavity Length Adjustments 
       Reply  Fri Jun 18 15:07:26 2010, Alberto, Update, LSC, Short Cavity Length Adjustments 
Message ID: 3086     Entry time: Fri Jun 18 13:47:20 2010     In reply to: 3084     Reply to this: 3087
Author: Koji 
Type: Update 
Category: LSC 
Subject: Short Cavity Length Adjustments 

You should have been in my lecture yesterday!
Power in the cavity is not a good index (=error signal) to judge the optimal length.
You should look at the phases of the length signals. (i.e. demodulation phase which gives you the maximum amplitude for CARM, PRC, SRC, etc)

You must move the SRC and PRC lengths at the same time.
The resonance of f1 (mostly) depends on the PRC length, but that of f2 depends on both the PRC and SRC lengths.

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