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Entry  Tue May 5 23:44:14 2020, gautam, Update, ASC, IMC WFS WFSmatrixComparison.pdfWFSheadNoise.pdf
    Reply  Thu May 7 09:43:21 2020, rana, Update, ASC, IMC WFS 
       Reply  Thu May 7 10:58:06 2020, gautam, Update, ASC, IMC WFS 
Message ID: 15321     Entry time: Thu May 7 10:58:06 2020     In reply to: 15320
Author: gautam 
Type: Update 
Category: ASC 
Subject: IMC WFS 

OK so the QPD segments are in the "+" orientation when the 40m IMC WFS heads are mounted at 45 deg. I thought "+" was the natural PIT/YAW basis but I guess in the the LIGO parlance, the "X" orientation was considered more natural.

Quote:

This is the doc from Keita Kawabe on why the WFS heads should be rotated.

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