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Entry  Tue Nov 13 22:12:15 2012, Jenne, Update, IOO, Turn off MCL path before doing MC spot measurement 
    Reply  Wed Nov 14 09:01:42 2012, Dumb statement catcher, Update, IOO, Turn off MCL path before doing MC spot measurement 
       Reply  Wed Nov 14 13:58:18 2012, Jenne, Update, IOO, Turn off MCL path before doing MC spot measurement 
Message ID: 7712     Entry time: Wed Nov 14 13:58:18 2012     In reply to: 7711
Author: Jenne 
Type: Update 
Category: IOO 
Subject: Turn off MCL path before doing MC spot measurement 

Quote:

Quote:

We have discovered that the MCL loop squishes the length fluctuations that result from the MC spot measurement angular dither.  This is good, in that the MCL is doing what it ought to do.  However, we need to turn it off before doing a spot measurement.

 This is totally non-sensical statement, of course.

We might also say that the DARM loop totally squishes the GW signal and so its better not to have any feedback in the interferometer.

 Hmmm, indeed.  To keep MC_L on, we should be looking at the control signal rather than the error signal.  I think Den has MC_L running nicely such that it always comes on when the MC locks, so I can switch it.

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