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Entry  Tue Jun 25 09:58:08 2013, Erica, Notes, fiber optic, mode matching refcav_mm.JPG
    Reply  Mon Jul 8 21:52:04 2013, tara, DailyProgress, optic, mode matching to refcavs 
       Reply  Tue Jul 9 19:35:20 2013, tara, DailyProgress, optic, beat board is back 
          Reply  Thu Jul 11 00:19:52 2013, tara, DailyProgress, optic, both cavities are locked photo_2013_07_10.JPG
Message ID: 1228     Entry time: Mon Jul 8 21:52:04 2013     In reply to: 1209     Reply to this: 1231
Author: tara 
Type: DailyProgress 
Category: optic 
Subject: mode matching to refcavs 

 I redid the mode matching for both refcav, the visibilities are up to ~ 93% and 95% for RCAV and ACAV.

  • For RCAV (refcav with PMC), the visibility was ~ 80% before, now it is ~95%. (The numbers are measured from the reflected beam on the RFPD)
  • For ACAV (refcav without PMC), the visibility is now ~ 93%. This is pretty good, compared to ~ less than 85% from previous setup when we used an AOM.

I'll add the new layout for the current situation soon.

 

==Note==

  • We care about mode matching because we already saw that any light that was not coupled into the cavity was reflected back to the laser and caused extra noise.
  • By changing the lens, the beams for fiber optic (both for Gyro and Erica's experiment) have to be re calculated. I'm sorry about that .
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