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Entry  Mon May 10 20:03:22 2010, Kevin, Update, Green Locking, Green Laser Beam Profile vbp.jpgvbp_residuals.jpghbp.jpghbp_residuals.jpg
    Reply  Mon May 10 22:25:03 2010, Koji, Update, Green Locking, Green Laser Beam Profile 
       Reply  Tue May 11 14:39:17 2010, Aidan, Update, Green Locking, Green Laser Beam Profile P5110057_beams.jpg
       Reply  Tue May 11 17:02:43 2010, Kevin, Update, Green Locking, Green Laser Beam Profile vbp.jpgvbp_residuals.jpghbp.jpghbp_residuals.jpg
          Reply  Wed May 12 03:42:38 2010, Koji, Update, Green Locking, Green Laser Beam Profile 
             Reply  Fri May 14 16:14:37 2010, Kevin, Update, Green Locking, Green Laser Beam Profile profile.pngresiduals.png
Message ID: 2912     Entry time: Tue May 11 17:02:43 2010     In reply to: 2909     Reply to this: 2916
Author: Kevin 
Type: Update 
Category: Green Locking 
Subject: Green Laser Beam Profile 

 

Quote:

Hey, what a quick work!

But, wait...

1) The radius of the beam was measured by the razor blade.

2) The diameter of the beam (13.5% full-width) at each point was measured by Beam Scan. The one at z=~7cm was consistent with 1)

3) The data 2) was fitted by a function w = sqrt(w0^2+lambda^2*(x-x0)^2/(pi*w0)^2). This is defined for the radius, isn't it?

So the fitting must be recalculated with correct radius.
Make sure that you always use radius and write with a explicit word "radius" in the record.

I recalculated the fits using the radius of the beam instead of the diameter of the beam at 13.5% full-width with the following results:

For the vertical beam profile:

reduced chi^2 = 3.25

x0 = (-86 ± 1)mm

w0 = (46.01 ± 0.38)µm

For the horizontal beam profile:

reduced chi^2 = 2.05

x0 = (-81 ± 1)mm

w0 = (45.50 ± 0.28)µm

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