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Entry  Thu Aug 28 18:56:14 2008, rana, Configuration, PSL, beam block distorted 
    Reply  Fri Aug 29 10:20:32 2008, Yoichi, Configuration, PSL, beam block distorted 
    Reply  Fri Aug 29 16:35:18 2008, Yoichi, Configuration, PSL, beam block distorted 
Message ID: 902     Entry time: Fri Aug 29 16:35:18 2008     In reply to: 893
Author: Yoichi 
Type: Configuration 
Category: PSL 
Subject: beam block distorted 

Quote:
There was a beam block after the Mach Zender. Who or what put this there?

The going to the MC now looks distorted as if someone has left something funny in the beam or maybe the new PMC has started to degrade??

Use the ELOG people...its good for you.


The apparent distortion of the MC refl. was caused by mis-alignment of the MC mirrors.
Because the MC1 was mis-aligned, the reflected light was clipped by a steering mirror.
I restored the MC angle bias values from the conlog history and now the MC locks.
According to conlog, the MC alignment was changed at around 18:30 on Thursday PDT.
It could have been caused by the computer reboots.
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