Luminosity Function
The number of galaxies in the luminosity range in a given volume is denoted . The observational approximation to the mean number of galaxies per unit volume brighter than absolute magnitude M measured by Hubble is ...
Luminosity Function
(a) The number of stars in the Galaxy with a particular absolute magnitude. The luminosity function reveals that luminous stars are rare and intrinsically faint stars common.
Luminosity Function - The distribution of stars or galaxies according to their luminosities. A luminosity function is often expressed as the number of objects per unit volume of space that are brighter than a given absolute magnitude or luminosity.
Luminosity Function (census by brightness)
lower luminosity stars more common
night sky stars usually luminous ...
Luminosity Function: The relative number of astronomical objects that have a certain luminosity. In the case of stars, the low luminosity stars are the most abundant, and the number of stars declines rapidly with increasing luminosity.
yÎ" is the standard luminosity function, JÎ" is the spectral power distribution of the radiant intensity.
The luminous coefficient is unity for a narrow band of wavelengths at 555 nanometres.
This distribution of globular cluster luminosities is called the Globular Cluster Luminosity Function (GCLF).
Globular-cluster luminosity functions - these work much like the planetary-nebula luminosity function technique.
The luminosity function reveals that luminous stars are rare and intrinsically faint stars common.
(b) The distribution of galaxies by absolute magnitude. Luminous galaxies are rare and intrinsically faint ones are common. [C95] ...
However, by looking at the more easily observed quasars in the nearby universe, and assuming that the luminosity function (number of quasars as a function of luminosity) during reionization will be approximately the same as it is today, ...
Then the luminosity of several things are calibrated: (a) the supernova type 1a maximum luminosity in any type of galaxy; (b) the globular cluster luminosity function in elliptical galaxies; ...
The total X-ray luminosity function of a cluster is much easier to measure than its MF, but it's a lot more complicated to interpret.
A Dictionary of Astronomy entry for luminosity function
A Dictionary of Astronomy entry for luminosity evolution
A Dictionary of Astronomy entry for luminosity class
A Dictionary of Astronomy entry for luminosity ...
Their study used the luminosity function of active galactic nuclei - galaxies with signs of non-stellar activity at their centres, attributed to the accretion of matter onto a black hole - with masses a million to a billion times that of our own Sun.
At a distance of 1 Mpc the apparent size of Antlia on the deep CCD images suggests that it is only 1-2 kpc in diameter and probably only contains a million or so stars placing it firmly at the faint end of the galaxy luminosity function.
 See also: Luminosity, Galaxies, Galaxy, Redshift, Emission
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