> Don't want to step on any radio astronomer's toes, but flux density
> is flux. Yes, I know, it's monochromatic flux per unit
> frequency, but where's the distinction between bolometric flux,
> monochromatic flux per unit frequency, and monochromatic flux per
> unit wavelength? Do we also then have to support the use of
> candela's, lux's, and the lot - also physical (even SI!) terms for
> the same things? How about (see, e.g., Mihalas):
>
> phot.flux generic net rate of radiant
> energy flow per unit area and time
> phot.flux.freq monochromatic flux per unit
> frequency, flux density
> phot.flux.wave monochromatic flux per unit wavelength
> phot.flux.bol bolometric flux
> phot.flux.Eddington Eddington flux = flux / 4PI
>
> I was going to suggest adding phot.flux.astr (that terrible factor
> of PI or /1PI, depending upon how you look at it!), but I won't......
Sorry - should have re-read the 1.02 documentation: "flux density" has been generalized beyond it's normal use. How do we then distinguish between the many different forms? By units alone, i.e. non-UCD things? That works fine for things like lengths and times and masses, since the physical quantities are well defined beyond their units, but F_nu and F_lambda are totally different quantities and this fact is utterly independent of the units.
Perhaps
phot.flux.perFreq
phot.flux.perWave
phot.flux.perEnergy
phot.flux.perWavenumber
phot.flux.perDecade nu*F_nu, lambda*F_lambda,...
Looking at the current list, I'd also like to complain about
phot.flux.sb
Since when is surface brightness a flux? Surface brightness is an intensity and intensity != flux. So...
phot.intensity generic directed
rate of radiant energy flow per unit area, time, and solid angle,
surface brightness
phot.intensity.bol (not generally
needed, but here for symmetry)
phot.intensity.perFreq
phot.intensity.perWave
phot.intensity.perEnergy
phot.intensity.perWavenumber
phot.intensity.perDecade (Ibid.)
I know this is a bit of a change, but I frankly didn't notice before.... sorry!
Rick Received on 2005-11-08Z10:54:13