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The protom flux

  1. Feb 14, 2012 #1
    Dear forum users,

    I have a quite simple question. I have got a flux of protons measured in 1/(cm^2 s sr), I would like to have it in 1/(cm^2 s).

    Best regards,
  2. jcsd
  3. Feb 16, 2012 #2
    Then you should multiple by the number of sr
  4. Feb 17, 2012 #3
    Yes, I have got problem with sr concept:p Lets say that the distance between source and the detector is 1m. My detector has effective area of 1 cm^2. So by how many sr I should multiply my flux?

    My answer would be:

    The area of the sphere with radius of 1m^2 is:

    [itex]S = 40000 \pi [cm^2][/itex]

    the effectiv area of the detector is D = 1cm^2, so:

    [itex]\frac{D}{S} = \frac{1}{40 000 \pi} = \frac{1}{125600} = 7.9 \times 10^{-6} [/itex]

    So the soild angle of my detector should be:

    [itex]θ_{D} = 4\pi \times 7.9 \times 10^{-6}[sr][/itex]

    So finally:

    [itex]θ_{D} = 9.92 \times 10^{-5} [sr][/itex]

    Am I right?

    Best regards,
    Last edited: Feb 17, 2012
  5. Feb 17, 2012 #4
    Yeah, I think that looks great!
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