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I think my problem may be a little trivial however I have been stuck on it for quite some time. I have plots of flux density (Jy) versus wavelength in order to look at a particular forbidden line. I want to find the luminosity of the line, however as I am dealing with Jy [W/(m^2 Hz)] I do not know how to deal with the frequency unit.

I am using the luminosity formula 4*pi*R^2*integral_flux_density. I am only looking at the main bit of the spectrum which I circle in the attached image.

I attempted to handle the Hz by multiplying my integral_flux_density by a correction value (s*λ^2)/c where s is the sampling value (the wavelength difference divided by the number of values) and c the speed of light. However the units do not work out.

I came up with my correction value based on:

Janksy unit = W m^-2 Hz^-1 (ignoring the 10^-26)

This is the same as dF/dv where v is nu the frequency symbol

I need dF/dv to go to dF/dλ

v=c/λ -> dv = - (c/λ^2) *dL

dF/dλ = dF/dv * dv/dλ

dF/dλ = - dF/dv * c/λ^2

dF/d\nu = -dF/dλ * (λ^2)/c

Any assistance would be greatly appreciated.

Thanks,

A :)

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# Flux Density (Jy) to Luminosity when wavelength is involved

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