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What is this equation

  1. Sep 20, 2009 #1
    What is this equation I[tex]\gamma[/tex]=([tex]\Gamma[/tex]N)/D2

    It is about Intensity of ray.
    But I can't find any information about it.
    What is it? And where can I get the information?
  2. jcsd
  3. Sep 20, 2009 #2


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    Hi ATPenergy! :smile:
    I'm not sure, but it looks a bit like irradiance = radiant flux (or radiant power) per area :confused:

    see http://en.wikipedia.org/wiki/Radiant_flux" [Broken]

    what book did you get it from?
    Last edited by a moderator: May 4, 2017
  4. Sep 21, 2009 #3
    i think it is the relation between natural line width, mean life time and Planck's constant!!!
    the correct relation which i know (FWHM)*meanlifetime=hbar.
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