40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
  40m Log  Not logged in ELOG logo
Message ID: 4652     Entry time: Fri May 6 14:59:36 2011
Author: Leo Singer 
Type: Configuration 
Category: SUS 
Subject: Tuning ITMY bandstop 

I tuned the ITMY bandstops -- 'before' and 'after' spectra attached.  Note that the after the tuning, the bounce mode at ~16 Hz is about twice as quiet!

 

However, notice that in the 'before' plot the roll mode at about 23.5 Hz did not show up at all, whereas it is quite prominent in the 'after' plot.  I was concerned that this line could have been a result of placing the bandstop there, so I made another plot with the BounceRoll filter turned off.  Sure enough, the 23.5 Hz line is still there.  So I'm not crazy: the roll mode did start acting up at some time between my 'before' and 'after' plot, but not as a result of the tuning.

Attachment 1: itmy-before.pdf  7 kB  | Hide | Hide all
itmy-before.pdf
Attachment 2: itmy-after.pdf  7 kB  | Hide | Hide all
itmy-after.pdf
Attachment 3: itmy-nobounceroll.pdf  7 kB  | Hide | Hide all
itmy-nobounceroll.pdf
ELOG V3.1.3-