On this web page, we see the so-called "swordy plot"


enter image description here

At an energy of $10^{12}\ eV=1\ TeV$, we read vertically $10^{-4}$.

The radius of earth is 6371 km : that makes $4\pi R^2=5.1\times 10^{14}\ sr$.

I deduce that the flux for $1\ TeV$ is : $5.1\times 10^{14} * 10^{-4}=51\times 10^9 m^{-2}.s^{-1}$.

But wikipedia claims at this energy : $1 m^{-2}.s^{-1}$.

Where is my mistake?

I don't know if the "GeV" is important in the vertical axis. But if I multiply by $10^9$, it will certain not help to go in the "good" value.

  • 1
    $\begingroup$ Also, you calculated surface area, not solid angle. $\endgroup$
    – J. Murray
    Jan 17, 2021 at 14:37
  • $\begingroup$ @J. Murray : thanks a lot for the explanations and reference $\endgroup$ Jan 17, 2021 at 14:49


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