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Entry  Wed May 26 00:50:16 2010, Jenne, Update, IOO, Mirrors moved in prep for round 2 of MC mode measuring 
    Reply  Wed May 26 14:28:01 2010, Koji, Update, IOO, Mirrors moved in prep for round 2 of MC mode measuring 
       Reply  Wed May 26 15:34:00 2010, Jenne, Update, IOO, Mirrors moved in prep for round 2 of MC mode measuring 
Message ID: 2993     Entry time: Wed May 26 15:34:00 2010     In reply to: 2991
Author: Jenne 
Type: Update 
Category: IOO 
Subject: Mirrors moved in prep for round 2 of MC mode measuring 

Quote:

That's true. But I thought that you measured the mode after those optics and the effect of them is already included.

So:

  • We need to model the transmissive optics in order to understand the measured mode which is different from the MC mode slightly.
  • We just can calculate the modes based on the measurement in order to figure out the realistic positions of the MMT1 and MMT2.

Quote:

Rana pointed out that the anticipated mode calculation should be modified to include the index of refraction of the crystals in the Faraday, and the polarizers in the Faraday.  This may affect where we should put MMT1, and so this should be completed before round 2 measurements are taken, so that we can move MMT1.

 

 Yes, the measured mode takes all of this into account.  But in Kevin's plot, where he compares 'measured' to 'expected', the expected doesn't take the Faraday optics into account.  So I should recalculate things to check how far off our measurement was from what we should expect, if I take the Faraday into account.  But for moving forward with things, I can just use the mode that we measured, to adjust (if necessary) the positions of MMT1 and MMT2.  All of the other transmissive optics (that I'm aware of) have already been included, such as the PRM and the BS.  This included already the air-glass curved interface on the PRM, etc.

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