Stefan-Boltzmann law

    Caption: A graph of the Stefan-Boltzmann law radiant flux (AKA flux) F (black line called j in the figure) and the frequency-integrated Wien's approximation flux F (blue line). The vertical axis is in watts/meter**2.

    The Stefan-Boltzmann law is

    F=σT4 ,

    where the Stefan-Boltzmann constant σ = (5.67037419 ...)*10**(-8) W/*m**2/K**4 (exact) (see NIST: Fundamental Physical Constants --- Complete Listing 2018 CODATA adjustment)) and T is temperature on the Kelvin scale.

    We can see that flux F increasing as the 4th power of temperature---a very strong increase with temperature.

    The frequency-integrated Wien's approximation is:

    F_Wien=F/ζ(4)=(0.9239384 ...)*F ,

    where ζ(s) is the Rieman zeta function and

    ζ(4)=π4/90 = 1.0823232 ... .

    This is NOT log-log plot, but it should be in order to show the behavior over the whole temperature range from 0 to 10**4 K.

    Credit/Permission: © User:Netheril96, 2011 / Creative Commons CC BY-SA 3.0.
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