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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: 865     Entry time: Wed Jul 21 20:13:06 2010     In reply to: 855     Reply to this: 867   870   873
Author: Dmass 
Type: Laser 
Category: PSL 
Subject: H1 NPRO Measured 

I want to lock with the NPRO laser PZT (as done at the 40m) - and thus want the transfer functions of the NPRO PZT to phase / amplitude modulation (measured by Mott @ the 40)

  • First plot attached is PZ T to AM response

I will use the 143.8kHz dip in the AM spectrum for locking (as sidebands), then later look at the PZT error signal to find the phase transfer function. I am interested in maximizing the ratio of PM/AM. For the loop:

  • I will put in a second order passive component low pass to filter out the 2f (at 10 kHz)
  • This is quick and should allow me to take my phase transfer function and tweak the setup if needed (and consider going to that 320ish kHz dip in the AM spectrum)
  • I may be able to live with a 1 kHz UGF, as I used a 600 - 800 Hz UGF when I ran with the old frontend

 

I have a question which I either don't know or can't remember the answer to:

  • Is there very little spatial distortion induced on the beam at these frequencies by using funny PZT resonances to lock, or do they exist and  we just don't care because they are out of band (presuming they aren't downconverted somehow)
Attachment 1: H1NPRO_AM.png  23 kB  Uploaded Wed Jul 21 21:32:58 2010  | Hide | Hide all
H1NPRO_AM.png
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