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Entry  Wed Jul 14 14:39:09 2010, Dmass, Laser, PSL, H1 NPRO Measured NPROWaist.pdf
    Reply  Thu Jul 15 15:41:40 2010, Dmass, Laser, PSL, H1 NPRO Measured 
       Reply  Fri Jul 16 18:54:57 2010, Dmass, Laser, PSL, H1 NPRO Measured H1ModeMSoln.pdf
          Reply  Sat Jul 17 01:41:20 2010, Koji, Laser, PSL, H1 NPRO Measured 
          Reply  Wed Jul 21 20:13:06 2010, Dmass, Laser, PSL, H1 NPRO Measured H1NPRO_AM.png
             Reply  Thu Jul 22 16:19:48 2010, Koji, Laser, PSL, H1 NPRO Measured 
             Reply  Fri Jul 23 00:45:46 2010, Dmass, Laser, PSL, H1 NPRO Measured 
                Reply  Tue Jul 27 00:10:20 2010, Dmass, Laser, PSL, PMC Calibrated PMCCtrl.pdf
             Reply  Tue Jul 27 19:04:35 2010, Dmass, Laser, PSL, H1 NPRO Measured NproPZTFMBode.pdf
                Reply  Wed Jul 28 19:51:10 2010, Dmass, Laser, PSL, H1 NPRO Measured IMG_0241.png
                   Reply  Fri Jul 30 16:48:11 2010, Dmass, Laser, PSL, H1 NPRO Measured 
                      Reply  Sun Aug 1 18:37:07 2010, Dmass, Laser, PSL, H1 NPRO Measured 
                   Reply  Mon Aug 2 00:46:13 2010, Dmass, Laser, PSL, H1 NPRO Measured Picture_2.png
    Reply  Mon Aug 2 22:23:36 2010, Dmass, Laser, PSL, H1 NPRO Measured H1MM2PMC.pdf
    Reply  Tue Aug 3 01:31:15 2010, Dmass, Laser, PSL, H1 NPRO Measured H1NPROWaist2.pdf
       Reply  Tue Aug 3 13:47:55 2010, Dmass, Laser, PSL, H1 NPRO Measured Npro2PMCmm.pdf
       Reply  Tue Aug 3 17:27:20 2010, Dmass, Laser, PSL, H1 NPRO Measured 
Message ID: 895     Entry time: Mon Aug 2 22:23:36 2010     In reply to: 852
Author: Dmass 
Type: Laser 
Category: PSL 
Subject: H1 NPRO Measured 

I had only 25% coupling through the PMC, so was double checking my mode matching with the wincamD.

  • Measurement of the H1NPRO beam profile
  • Proposed mode matching solution (updated)
    • I double checked my mode matching solution with a program Frank put on fb1 (called mm.exe, under /home/controls) from one of the Germans. The results were consistent.
    • The mode I get at the PMC is WAY OFF from what it should be. ~750-800 um waist radius...
    • I saw this inconsistency on the first iteration of mode matching as well, and just tuned the mirrors by hand using the wincamD to make it 370 um and put it in the right place.
    • I had about 25% coupling max with the previous iteration.

I took some profiles with the WINCAMD of the transmission through one of the steering mirrors, and noticed that my fit didn't seem to....fit. This seems consistent with having a high M^2...Some notes on the measurement:

  • WinCam did not seems saturated (no white area on the CCD 2d color scale image)
  • Bleeding (blooming?) on CCD not on either measurement axis (also was not large)
  • used X orientation of the U and V axes for getting waists

IF I DOUBLE CHECK MY MEASUREMENT OF THE H1NPRO WAIST SIZE / LOCATION, AND CONFIRM IT, WHAT DOES THIS ALL MEAN FOR ME?

The fear: There is just loads of higher order content in the beam, and only 25% of the power is in the TEM00...

 

From Frank - if it's the alignment of the pump diodes inside the NPRO, we can see this quickly by opening up the NPRO. I do not desire to do this before I finish my paper/experiment.

 

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