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Entry  Tue Oct 30 00:47:29 2007, rana, Other, IOO, MC Ringdowns tek00000.pngtek00001.pngtek00004.pngMC2ringdown.tar.gz
    Reply  Tue Oct 30 13:58:07 2007, ajw, Configuration, IOO, MC Ringdowns CavityRingdown.pngCavityRingdown.m
Message ID: 30     Entry time: Tue Oct 30 13:58:07 2007     In reply to: 29
Author: ajw 
Type: Configuration 
Category: IOO 
Subject: MC Ringdowns 
Here's a quick fit-by-eye to the latter part of the data from tek00000.xls.

The prediction (blue) is eqn 41 of
http://www.ligo.caltech.edu/docs/P/P000017-A.pdf

T1 = T2 = 0.002. Loss1 = Loss2 = 150 ppm.
MC3 assumed perfectly reflecting.
Velocity = 320 um/s (assumed constant), 2 usec into the ringdown.

OK, there's one little fudge factor in the prediction:
I multiplied D by 2.
Attachment 1: CavityRingdown.png  8 kB  | Hide | Hide all
CavityRingdown.png
Attachment 2: CavityRingdown.m  2 kB  Uploaded Wed Nov 7 16:00:47 2007  | Hide | Hide all
% CavityRingdown.m
% Eqn 41 of 
% "Doppler-induced dynamics of fields in Fabry–Perot
% cavities with suspended mirrors", Malik Rakhmanov (2000).
% http://www.ligo.caltech.edu/docs/P/P000017-A.pdf

clear all

% read in ringdown timeseries:
at = importdata('tek00000.csv');
... 121 more lines ...
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