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Entry  Fri Apr 12 02:56:34 2013, Den, Update, Locking, prcl angular motion pointing.pngoplev_exc.pdf
    Reply  Fri Apr 12 09:20:32 2013, rana, Update, Locking, prcl angular motion 
       Reply  Fri Apr 12 13:21:34 2013, Den, Update, Locking, prcl angular motion 
          Reply  Sat Apr 13 03:45:51 2013, rana, Update, Locking, prcl angular motion 
             Reply  Sat Apr 13 23:11:04 2013, Den, Update, Locking, prcl angular motion pointing.pdf
                Reply  Sun Apr 14 17:56:03 2013, rana, Update, Locking, prcl angular motion 
                Reply  Mon May 13 18:44:04 2013, Jenne, Update, Locking, prcl angular motion TT_Q_measurements.pdf
Message ID: 8449     Entry time: Fri Apr 12 13:21:34 2013     In reply to: 8447     Reply to this: 8450
Author: Den 
Type: Update 
Category: Locking 
Subject: prcl angular motion 

Quote:

 How is the cavity g-factor accounted for in this calculation?

 I assume that pointing noise and dc misalignment couples 00 to 01 by a factor theta / theta_cavity

Inside the cavity 01 is suppressed by 2/pi*F*sin(arccos(sqrt(g_cav))).

For the XARM this number is 116 taking g-factor to be 0.32. So all pointing noise couples to power RIN.

Suppression factor inside PRC is 6.5 for g-factor 0.97. This means that 85% of jitter couples to RIN, I accounted for this factor while converting RIN to angle.

I did not consider translational motion of the beam. But still PRC RIN can not be explained by oples readings as we can see exciting optics in pitch and yaw. I suspect this RIN is due to PR3, as it can create stronger motion in yaw than in pitch due to incident angle and translational motion of the mirror. I do not have a number yet.

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