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Entry  Tue Jul 29 01:03:17 2008, rob, Configuration, IOO, MC length measurement 
    Reply  Tue Jul 29 09:12:43 2008, Koji, Configuration, IOO, MC length measurement 
Message ID: 753     Entry time: Tue Jul 29 09:12:43 2008     In reply to: 752
Author: Koji 
Type: Configuration 
Category: IOO 
Subject: MC length measurement 
I found that the prev modulation freq had been determined with a same kind of measurement by Osamu, which also looked accurate.
http://www.ldas-sw.ligo.caltech.edu/ilog/pub/ilog.cgi?group=40m&task=view&date_to_view=09/12/2002&anchor_to_scroll_to=2002:09:12:17:10:30-ajw

(There is also a document by Dennis to note about this measurement
http://www.ligo.caltech.edu/docs/T/T020147-00.pdf )

So, it means that the round trip length of the MC shortened by 1mm in the 6 years.
New              OLD
--------------------------
27.0924          27.0934    [m]

Quote:
rob, yoichi

We measured the length of the mode cleaner tonight, using a variant of the Sigg-Frolov method.
....
The new f2 frequency is:
New              OLD
--------------------------
165983145        165977195
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