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Entry  Mon Apr 16 16:23:09 2018, awade, DailyProgress, scatter, Beam size on trans BN detector IMG_2792.JPG20180416_RazorBladeProfileVerticalTransBNDector.pdf20180416_BeamProfileAtPD.ipynb.zip
    Reply  Thu Apr 19 18:28:11 2018, rana, DailyProgress, scatter, Beam size on trans BN detector 
       Reply  Sun Apr 22 22:00:15 2018, awade, DailyProgress, scatter, Switching out NF1811 detector for KA25MHz 
Message ID: 2174     Entry time: Thu Apr 19 18:28:11 2018     In reply to: 2172     Reply to this: 2176
Author: rana 
Type: DailyProgress 
Category: scatter 
Subject: Beam size on trans BN detector 

no This beam is WAY too big for the PD. If the beam radius (wz) is 100 microns and the PD active area diameter is 300 microns, than you're always scattering a lot of beam off of the metal of the can. For new focus 1811, the beam radius should be ~30-50 microns.

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