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Entry  Tue May 25 17:04:37 2010, Kevin, Update, , Beam Profile After Mode Cleaner mcfit.pngmcerrors.png
    Reply  Tue May 25 17:09:22 2010, Koji, Update, IOO, Beam Profile After Mode Cleaner 
       Reply  Tue May 25 17:22:56 2010, Kevin, Update, IOO, Beam Profile After Mode Cleaner mcfit.png
Message ID: 2984     Entry time: Tue May 25 17:04:37 2010     Reply to this: 2985
Author: Kevin 
Type: Update 
Category:  
Subject: Beam Profile After Mode Cleaner 

I fit the data from the beam profile that Jenne measured on 5/21/2010. The distances are measured from halfway between MC1 and MC3 to the beam scanner. The fits give the following where w0 is the waist size and z0 is the distance from the waist to halfway between MC1 and MC3.

For the horizontal profile:

reduced chi^2 = 0.88

z0 = (1 ± 29) mm

w0 = (1.51 ± 0.01) mm

For the vertical profile:

reduced chi^2 = 0.94

z0 = (673 ± 28) mm

w0 = (1.59 ± 0.01) mm

I calculated the radius of curvature of MC2 using these values of w0:

horizontal: (16.89 ± 0.06) m

vertical:   (17.66 ± 0.07) m

For this calculation, I used the value of (13.546 ± .0005) m for the length of the mode cleaner measured on 6/10/2009. The specification for the radius of curvature of MC2 is (18.4 ± 0.1) m.

In the following plots, the blue curve is the fit to the vertical beam radius, the purple curve is the fit to the horizontal beam radius, * denotes a data point from the vertical data, and + denotes a data point from the horizontal data.

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mcerrors.png
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