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Message ID: 1147     Entry time: Mon Nov 8 00:21:43 2010
Author: Zach 
Type: Laser 
Category: GYRO 
Subject: Primary loop unsuppressed frequency noise 

Below is a comparison of the "unsuppressed" primary loop frequency noise with the free-running NPRO noise taken from Rana's thesis (p.80). The primary error signal was multiplied by the OLTF to obtain the unsuppressed voltage noise at the servo input, and this was then divided by the cavity response quoted in the previous elog post to obtain the unsuppressed noise in Hz. The plot shows that the gyro cavity displacement noise is ~10-100x higher than the free-running laser noise up to a few kHz.

unsup_freq_noise.png

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