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Entry  Thu Oct 18 01:20:49 2012, tara, DailyProgress, NoiseBudget, Thermoelastic noise in spacer 
    Reply  Wed Oct 24 20:22:01 2012, tara, DailyProgress, NoiseBudget, Thermoelastic noise in spacer dmasscavity_sagging_0_2012_10_04.pngshort_nb.png
Message ID: 1064     Entry time: Thu Oct 18 01:20:49 2012     Reply to this: 1066
Author: tara 
Type: DailyProgress 
Category: NoiseBudget 
Subject: Thermoelastic noise in spacer 

I talked to Jan about how to calculate thermoelastic (TE) noise in a spacer. I will use comsol to estimate the thermoelastic noise in our cavity.

  Thermoelastic noise has not been estimated for our setup. I think it will not be that high. As the previous result with 8" cavity, the measured signal was very close to the estimated coating Brownian noise. However, our noise budget will be more comprehensive if we include TE noise in the spacer.

 Basically to do that, we have to apply force on the spacer , then calculate the gradient of the strain inside the spacer [Liu and Thorne, 2000]. I think this can be done by COMSOL. I am working on it. I'll add more details on CTN wiki page later.


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