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Entry  Wed Feb 6 11:59:12 2013, Jenne, Update, Locking, PRC cavity gains 
    Reply  Wed Feb 6 18:39:08 2013, Jenne, Update, Locking, PRC cavity gains 
       Reply  Wed Feb 6 19:59:35 2013, rana, Update, Locking, PRC cavity gains 
          Reply  Wed Feb 6 20:03:50 2013, Manasa, Update, Locking, PRC cavity gains 
       Reply  Wed Feb 13 14:21:19 2013, Jenne, Update, Locking, PRC cavity gains 
Message ID: 8076     Entry time: Wed Feb 13 14:21:19 2013     In reply to: 8014
Author: Jenne 
Type: Update 
Category: Locking 
Subject: PRC cavity gains 

Quote:

With 1500ppm loss on both PR2 and PR3, 150ppm arm cavity loss:

We get a PRC gain for the CARRIER (non-flipped folding) of 21, and PRC gain (flipped folding) of 20.  This is a 4.7% loss of carrier buildup.

We get a PRC gain for the SIDEBANDS (non-flipped folding) of 69, and PRC gain (flipped folding) of 62.  This is an 8.8% loss of sideband buildup.

 With a PR2 loss of 896ppm (from the plot on the wiki), but no loss from PR3 because we didn't flip it, and the same 150ppm round trip arm cavity loss, I get:

Carrier gain = 21.0

Sideband gain = 66.7

(No loss case, with an extra sig-fig, so you can see that the numbers are different:  Carrier = 21.4, Sideband = 68.8 .)

So, this is 1.6% loss of carrier buildup and 3.1% loss of sideband buildup.  Moral of the story - G&H's measured AR reflectivity is less than Rana's guess, and we didn't flip PR3, so we should have even less of a power recycling gain effect than previously calculated.

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