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Entry  Fri Dec 10 01:14:08 2010, tara, Summary, RefCav, RCAV/ACAV poles acav_pole.pngrcav_pole.png
    Reply  Fri Dec 10 12:07:34 2010, Frank, Summary, RefCav, RCAV/ACAV poles 
Message ID: 424     Entry time: Fri Dec 10 01:14:08 2010     Reply to this: 425
Author: tara 
Type: Summary 
Category: RefCav 
Subject: RCAV/ACAV poles 

I analyzed the pole for RCAV and ACAV from 2010_12_06 entry. ACAV has a pole at  54 kHz, RCAV pole is at 38kHz.

 

Cavity pole = FWHM/2. Knowing cavity pole and FSR, we can calculate a cavity's finesse (= FSR/ pole). These values

will be used when we simulate the TF of the system

We amplitude modulated the laser intensity via EAOM, and measured the TF between RCAV_trans_PD and PMC for RCAV pole.

Since PMC's pole is ~2 MHz and ACAV/RCAV poles should be around 35 MHz, PMC won't effect much on our measurement.

 

Cavity is 0.2032 m long -> FSR = c/2L = 738 MHz, then

 

ACAV's Finesse = FSR/FWHM = 6835

RCAV's Finesse =  9710

 

 

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