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Entry  Tue Nov 30 21:48:13 2010, tara, DailyProgress, RefCav, Cavities egienmode cavity_mode.png
    Reply  Tue Nov 30 22:41:31 2010, rana, DailyProgress, RefCav, Cavities egienmode 
Message ID: 412     Entry time: Tue Nov 30 21:48:13 2010     Reply to this: 413
Author: tara 
Type: DailyProgress 
Category: RefCav 
Subject: Cavities egienmode 

I measured the beat signal and VCO feedback signal to see a peak from cavities' mode of vibration, there are 4 peaks from 1kHz to 20kHz.

 

We expect to see  the cavities' resonance around 10k Hz with high Q, say 10^6. I measured the beat signal and VCO feed back to double check my results.

There are 4 peaks, 5.98 kHz, 10.28 kHz, 12.8 kHz, and 13.85 kHz, that coincide. However, the peaks do not look sharp (Q is too low), and the FWHM

of peaks at 5.98kHz and 13.85kHz might be too broad to be the cavities' mode. So 10.28 and 12.8 seem to be good candidates.

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