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Message ID: 4     Entry time: Thu May 2 14:00:36 2013
Author: Koji 
Type: General 
Category: Configuration 
Subject: test mass TR with Levin's approach 

Thermo-refractive noise in a finite cylindrical/infinite test mass with Levin's approach

Location of the codes: 40m SVN repository

This code realizes Levin's calculation on thermo-refractive noise
and duplicates the result of D. Heinerts paper
DOI: 10.1103/PhysRevD.84.062001
Also the result is compared with Braginsky's result in 2004.

- The code applies gaussian-shaped heat into a cylindrical mirror.

- The heating/cooling is sinusoidal and the dissipation (heat flow) is calculated in COMSOL.

- The time series result was analyzed in MATLAB to extract the single coefficient corresponds to the transfer function.
This way the effect of the initial transient was avoided.

- Unfortunately direct measurement of frequency response in COMSOL was not available as the heat flow is not modal.
If we make a fourier analysis of the partial differential equation and solve it in COMSOL using arbitrary PDE solver,
we may turn this time dependent analysis into static analysis.

All of the calculation was driven from MATLAB. So you have to launch "COMSOL with MATLAB".

Attachment 1: thermo_refractive_1D_axisym_result.pdf  70 kB  Uploaded Thu May 2 15:02:35 2013  | Hide | Hide all
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