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Entry  Fri Feb 8 23:59:42 2013, yuta, Update, Locking, PR2-flipped half-PRC mode scan halfPRCmodescan.png
    Reply  Sat Feb 9 11:25:35 2013, Koji, Update, Locking, PR2-flipped half-PRC mode scan 
       Reply  Sun Feb 10 17:30:39 2013, yuta, Update, Locking, PR2-flipped half-PRC mode scan modescan_pitmisalign.pngmodescan_yawmisalign.png
          Reply  Mon Feb 11 13:15:16 2013, yuta, Update, Locking, PR2-flipped half-PRC mode scan 
          Reply  Mon Feb 11 21:03:15 2013, yuta, Update, Locking, PR2-flipped half-PRC mode scan modespacing_pit.pngmodespacing_yaw.png
Message ID: 8050     Entry time: Sat Feb 9 11:25:35 2013     In reply to: 8049     Reply to this: 8052
Author: Koji 
Type: Update 
Category: Locking 
Subject: PR2-flipped half-PRC mode scan 

Don't  Shouldn't you apply a small misalignment to the input beam? Isn't that why the peak for the 1st-order is such small?

Quote:

Method
 1. Aligned half-PRC using input TT1 and TT2 by maximizing POP DC during lock. It was not so easy because POP DC fluctuates much at ~ 3 Hz with amplitude of ~ 30 % of the maximum value because of the beam motion (movie on  elog #8039).

 2. Unlocked half-PRC and took POP DC and PRC error signal data;

> /opt/rtcds/caltech/c1/scripts/general/getdata -d 1 -o /users/yuta/scripts/PRCmodescan C1:LSC-POPDC_OUT C1:LSC-REFL11_I_ERR

  Ran again and again until I get sufficiently linear swing through upper/lower sidebands.

 

ELOG V3.1.3-