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Entry  Thu Nov 12 18:01:10 2009, Frank, Things to Buy, RefCav, heaters for the other two chambers 
    Reply  Thu Nov 12 20:56:38 2009, rana, Things to Buy, RefCav, heaters for the other two chambers 
       Reply  Fri Nov 13 10:56:32 2009, Frank, Things to Buy, RefCav, heaters for the other two chambers 
          Reply  Fri Nov 13 12:46:35 2009, rana, Misc, RefCav, heaters for the other two chambers 
             Reply  Tue Nov 17 12:01:54 2009, Frank, Misc, RefCav, heaters for the other two chambers 
Message ID: 12     Entry time: Fri Nov 13 12:46:35 2009     In reply to: 10     Reply to this: 13
Author: rana 
Type: Misc 
Category: RefCav 
Subject: heaters for the other two chambers 

For the heater, my main concern is on the residual thermal gradients after stabilization. The Alnis, Hansch, et al papers described how they had trouble with using multiple heaters and multiple sensors.

Our experience from the 40m is also that the single out of loop sensor (AD590) shows a much larger signal than the residual in-loop noise. This is only an issue below 10 mHz, so its not worth worrying about if it makes things take longer in the near term.

 

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