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Entry  Tue Aug 9 02:44:32 2011, Suresh, Update, SUS, ETMX free swinging data ETMX_freeswing.png
    Reply  Tue Aug 9 11:33:33 2011, kiwamu, Update, SUS, Re: ETMX free swinging data 
Message ID: 5153     Entry time: Tue Aug 9 11:33:33 2011     In reply to: 5150
Author: kiwamu 
Type: Update 
Category: SUS 
Subject: Re: ETMX free swinging data 

I believe that the 17 Hz broad structure on SIDE is just because of a bad rotational angle of the SIDE OSEM.

The same structure had been observed on the EMTY_UR, and the structure became narrower after we repositioned/rotated the OSEM yesterday.

My guess is that the SIDE OSEM is now in a place where the OSEM is quite sensitive to the bounce mode

and creating the broad structure due to a bi-linear coupling between the bounce mode and low frequency signals.

Quote from #5150

There is something defintely wrong with the side sensor.  It might be the electronics as it also has this problem with it slow channel readings (my previous elog today). 

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