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Entry  Mon Apr 2 18:24:34 2012, keiko, Update, LSC, RAM simulation for Full ifo 
    Reply  Tue Apr 3 01:52:15 2012, Zach, Update, LSC, RAM simulation for Full ifo 
       Reply  Tue Apr 3 14:11:33 2012, keiko, Update, LSC, RAM simulation for Full ifo 
    Reply  Tue Apr 3 14:17:18 2012, keiko, Update, LSC, RAM simulation for Full ifo flowchart.png
       Reply  Tue Apr 3 15:50:58 2012, keiko, Update, LSC, RAM simulation for Full ifo 
          Reply  Tue Apr 3 22:50:37 2012, keiko, Update, LSC, RAM simulation for Full ifo 
             Reply  Wed Apr 4 23:57:35 2012, keiko, Update, LSC, RAM simulation for Full ifo 
                Reply  Sat Apr 7 00:31:12 2012, keiko, Update, LSC, RAM simulation for Full ifo plot4a.pngplot4b.png
Message ID: 6504     Entry time: Sat Apr 7 00:31:12 2012     In reply to: 6486
Author: keiko 
Type: Update 
Category: LSC 
Subject: RAM simulation for Full ifo 

I didn't understand how CARM can be decreased 2 orderes of magnitude and PRCL can be INCREASED by such small offsets (see the matrix quoted).

Apparently it was because of an optical-spring ish effect from the "detuning" (which is actually RAM position offsets). I put two plots which are CARM and PRCL tranfer functions to REFL f1 or POP f1, when there is a slight PRCL offset (0, 1e-14m, and 1e-15m cases are plotted). Looking at these plots, it was not a good idea to calculate the LSC matrix in DC because they are affected by this detuning a lot. I'll try f = 150 Hz for the matrix.

plot4a.pngplot4b.png

Quote:

*** Iteration *** 

%*.*.*. Resulting matrix w/ RAM .*.*.*

REFL f1 : 0.039125    -0.000000    0.003665       0.000005    -0.000007 

  AS f2 : 0.000010    1.000431    0.000009       -0.003500    -0.000002 

 POP f1 : 156.420221    -0.000246    15.586838    0.019406    -0.000154 

 POP f2 : 1.255806    -0.154275    0.047313       1.000008    0.024285 

 POP f2 : -34.814720    -0.006600    -1.884850    0.042950    1.000000 

Offsets converged to:

PRCL =  2.1e-15, MICH = 1.1e-17, SRCL = -3.8e-15, CARM = 2.2e-16, DARM = 0  

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