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Message ID: 343     Entry time: Sun Sep 5 20:54:11 2010
Author: tara 
Type: Notes 
Category: NoiseBudget 
Subject: RIN from PMC and RCAV 

 SInce the Faraday isolator alter the beam path and beam profile a bit. The mode matching efficiency drops.

I only realigned the beam to PMC and RCAV. Lenses before PMC haven't been moved yet.

                    efficiency (P_in/P_out)              DC level (from PD behind the cavity)

PMC        18.2mW/27.9mW = 65%                   2.5V

RCAV       4.56/4.94 [mW]  = 92% (this drops from ~96%)    1.3V

 

pmc_n and rc_n (blue/green) were taken together with Faraday isolator installed .

 

pmc and rc with no isolator (purple/brown) are data from Aug 30, 2010.    

 

pmc blocked (red)  is PMC RIN when the beam after the PMC is blocked, RCAV loop disabled, SLOWDC control is disabled.

There is no significant change here, I have to think about it.

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