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Entry  Tue Aug 28 18:28:21 2012, janosch, Metaphysics, Ringdown, ripples  
    Reply  Tue Aug 28 19:06:32 2012, Koji, Metaphysics, Ringdown, ripples  
       Reply  Tue Aug 28 19:21:37 2012, janosch, Metaphysics, Ringdown, ripples  
          Reply  Tue Aug 28 20:23:54 2012, Koji, Metaphysics, Ringdown, ripples  
             Reply  Wed Aug 29 09:35:03 2012, janosch, Metaphysics, Ringdown, ripples 2 
                Reply  Fri Aug 31 17:44:21 2012, Manasa, Update, Ringdown, Data cum_plot.png
Message ID: 7305     Entry time: Wed Aug 29 09:35:03 2012     In reply to: 7304     Reply to this: 7330
Author: janosch 
Type: Metaphysics 
Category: Ringdown 
Subject: ripples 2 

Ok, so the whole idea that mirror motion can explain the ripples is nonsense. At least, when you think off the ringdown with "pump off". The phase shifts that I tried to estimate from longitudinal and tilt mirror motion are defined against a non-existing reference. So I guess that I have to click on the link that Koji posted...

Just to mention, for the tilt phase shift (yes, there is one, but the exact expression has two more factors in the equation I posted), it does not matter, which mirror tilts. So even for a lower bound on the ripple time, my equation was incorrect. It should have the sum over all three initial tilt angles not only the two "shooting into the long arms" of the MC.


Laser frequency shift = longitudinal motion of the mirrors

Ringing: http://www.opticsinfobase.org/ol/abstract.cfm?uri=ol-20-24-2463


Hmm. I don't know what ringing really is. Ok, let's assume it has to do with the pump... I don't see how the pump laser could produce these ripples. They have large amplitudes and so I always suspected something happening to the intracavity field. Therefore I was looking for effects that would change resonance conditions of the intracavity field during ringdown. Tilt motion seemed to be one explanation to me, but it may be a bit too slow (not sure yet). Longitudinal mirror motion is certainly too slow. What else could there be?



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