Frederic V. "Rick" Hessman hessman at Astro.physik.Uni-Goettingen.DE
Tue Nov 8 01:28:59 PST 2005


>
>>    Present                       Suggested new
>> E | phot.fluxDens               | phot.flux.fluxDens  or:
>> phot.flux.density
>> E | phot.fluxDens.sb            | phot.flux.fluxDens.sb  or:
>> phot.flux.density.sb
>>
>
> I agree that the second choices phot.flux.density.* are better.
> (Pierre - I don't think losing the fluxDens atom is a problem.)

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......

>>> Q | phys.massToLight            | phys.mass.light
>>>
> I don't like this, since it's not a mass, it's a ratio.
> It's really talking about the composition of the physical
> environment (how much baryons, how much photons, etc.)
> Maybe phys.composition.massLight (or phys.abund.massLight)

I prefer phys.composition.massLightRatio

Rick
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