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Entry  Tue Apr 30 01:15:26 2013, tara, Notes, NoiseBudget, AlAs/GaAs layer structure optimized for TO 
    Reply  Thu May 2 03:03:48 2013, tara, Notes, NoiseBudget, AlAs/GaAs layer structure optimized for TO 
       Reply  Thu May 2 23:40:46 2013, tara, Notes, NoiseBudget, AlAs/GaAs layer structure optimized for TO 6x
          Reply  Mon May 6 03:11:44 2013, tara, Notes, NoiseBudget, AlAs/GaAs layer structure optimized for TO RefCav_AlGaAs_TOnoise.png
             Reply  Mon May 6 17:08:25 2013, Matt A., Notes, NoiseBudget, AlAs/GaAs layer structure optimized for TO 
             Reply  Tue May 14 02:06:15 2013, tara, Notes, NoiseBudget, AlAs/GaAs layer structure optimized for TO 
                Reply  Wed May 15 20:07:12 2013, tara, Notes, NoiseBudget, AlAs/GaAs layer structure optimized for TO TO_compare_cap.pngTO_compare_cap.fig
                   Reply  Tue May 21 01:06:43 2013, tara, Notes, NoiseBudget, AlAs/GaAs layer structure optimized for TO 
                      Reply  Wed May 22 00:04:48 2013, tara, Notes, NoiseBudget, AlAs/GaAs layer structure optimized for TO 
                         Reply  Fri May 24 04:04:58 2013, tara, Notes, NoiseBudget, AlAs/GaAs layer structure optimized for TO 
                            Reply  Fri May 24 23:57:27 2013, tara, Notes, NoiseBudget, AlAs/GaAs layer structure optimized for TO 6x
                               Reply  Wed Jun 5 22:25:28 2013, tara, Notes, NoiseBudget, TO calculation review 
                         Reply  Thu Jun 6 22:28:46 2013, tara, Notes, NoiseBudget, AlAs/GaAs layer structure optimized for TO eighth.png
                            Reply  Tue Jun 11 00:45:48 2013, tara, Notes, NoiseBudget, noisebudget for 8" SiO2/Ta2O5 cavity sk2009nb.pngsk2009nb.fig
                               Reply  Tue Jun 11 16:46:52 2013, tara, Notes, NoiseBudget, noisebudget for 8" SiO2/Ta2O5 cavity getCoatBrownian2.m.zip
                               Reply  Wed Jun 12 01:34:27 2013, Koji, Notes, NoiseBudget, noisebudget for 8" SiO2/Ta2O5 cavity 
                                  Reply  Wed Jun 12 14:32:22 2013, not Koji, Notes, NoiseBudget, noisebudget for 8" SiO2/Ta2O5 cavity 
                                     Reply  Wed Jun 12 14:49:47 2013, Koji, Notes, NoiseBudget, noisebudget for 8" SiO2/Ta2O5 cavity 
                                        Reply  Fri Jun 14 02:36:22 2013, tara, Notes, NoiseBudget, noisebudget for 8" SiO2/Ta2O5 cavity 
                                           Reply  Tue Jun 18 11:53:17 2013, tara, Notes, NoiseBudget, noisebudget for 8" SiO2/Ta2O5 cavity spacer_br_8_edge.png
                            Reply  Mon Jul 15 10:55:40 2013, tara, Notes, NoiseBudget, AlAs/GaAs layer structure optimized for TO alGaAsnb.pngalGaAsnb.fig
Message ID: 1198     Entry time: Fri Jun 14 02:36:22 2013     In reply to: 1197     Reply to this: 1199
Author: tara 
Type: Notes 
Category: NoiseBudget 
Subject: noisebudget for 8" SiO2/Ta2O5 cavity 

I'm checking the result for the calculation.  I think it is too early to celebrate.

Nic suggested that I should use comsol to estimate the coating Brownian noise. There are a few problems:

  • For 3D model, I cannot mesh the geometry properly yet. The layer is too small for the rest of the mirror.
  • For 2D model, I cannot integrate the elastic energy from the coating layer. There is no choice to select the domain I want to integrate. I'll find out what happen.

I double checked the calculation code. I changed m to 65, and stepsize to w0/4000, the elastic energy (U) calculated is still ~ 1.5e-10 J. It did not change much from my last calculation. However, what I do not understand is the analytical result for half-infinite mirror (as given in SK2009 but different from GWINC), the number does not change that much.

I found a missing 2pi factor that causes the estimated noise to be higher and to match the measurement.  I'll check the calculation carefully again, but it might be that it's still not coating noise.

 

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