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Can you tell me if there is any difference between these 2 units?

$\log(\mathrm{quanta/cm^2/s})$ vs $\log(\mathrm{photons/cm^2/s})$.

Qmechanic
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az_
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1 Answers1

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"Number of photons" and "Number of quanta" are both dimensionless so

"quanta" cm$^{-2}$ s$^{-1}$ has the same units as "photons" cm$^{-2}$ s$^{-1}$.

But strictly, both expressions are wrong since:

$\log{x}= (x-1) - (1/2)(x-1)^2 + (1/3)(x-1)^3 - (1/4)(x-1)^4 + ...$

So the argument inside the logarithm should be unit-less.

Gyromagnetic
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