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Entry  Wed Jan 10 12:42:27 2018, gautam, Update, SUS, ETMX DC alignment ETMXdrift.png
    Reply  Wed Jan 10 18:53:31 2018, gautam, Update, SUS, ETMX DC alignment ETMXdrift.png
       Reply  Wed Jan 10 22:19:44 2018, rana, Update, SUS, ETMX DC alignment 
Message ID: 13527     Entry time: Wed Jan 10 18:53:31 2018     In reply to: 13523     Reply to this: 13528
Author: gautam 
Type: Update 
Category: SUS 
Subject: ETMX DC alignment 

I should've put in the SUSPIT and SUSYAW channels in the previous screenshot. I re-aligned ETMX till I could see IR flashes in the arm, and also was able to lock the green beam on a TEM00 mode with reasonable transmission. As I suspected, this brought the Oplev spot back near the center of it's QPD. But the answer to the question "How much did I move the ETM by" still varies by ~1 order of magnitude, depending on if you believe the OSEM SUSPIT and SUSYAW signals, or the Oplev error signals - I don't know which, if any, of these, are calibrated.

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ETMXdrift.png
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