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Message ID: 2189     Entry time: Wed May 16 10:40:06 2018
Author: anchal 
Type: DailyProgress 
Category: BEAT 
Subject: Installed Beatnote detector with known beam width at the point 

Using the result of the beam profile analysis, I calculated the required position and lens to put in to decrease beam width to about 300 um at the RFPD (1/3 of detector size 2mmx2mm). Attached matlab code for the same. I used a 687.5 mm Fused Silica lens for this purpose. Finally, I installed the beatnote detector after taking beam profiles with the beam profiler and finding the right position. Attached is the screenshot of the beam profile at this position shows that beam has a width of ~300 um. I have positioned the RFPD such that beam is incident at 30 degrees from normal on it.

Attachment 1: Images.pdf  1012 kB  Uploaded Wed May 16 20:06:05 2018  | Hide | Hide all
Images.pdf Images.pdf Images.pdf
Attachment 2: RFPDpositioning.zip  821 kB  Uploaded Wed May 16 20:06:13 2018
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