Galaxies metallicity-luminosity relation

The Metallicity-Luminosity Relation for Local Group Dwarf Galaxies... 

When the light is dominated by massive stars, e.g. in starburst galaxies, the luminosity is related in turn to the rate of metal production, since virtually all processed material is ejected in the form of metals (and some helium). Thus there is a relationship between the total co-moving luminosity density, the monochromatic luminosity density (deduced from star-forming galaxy redshift surveys with appropriate corrections for absorption) in a fixed frequency bandwidth (anywhere between 912 and about 2000 A in the rest frame) and the mass going into nucleosynthesis ... 

The basic data for stochastic simulations of galaxies and their constituent populations and metallicity evolution is the initial mass function (IMF), which represents the mass distribution with which stars are presumed to form. Its derivation from the observed distribution of luminosity among field stars (refs. 57 and 58 and references therein) and from star clusters involves many detailed corrections for both stellar evolution and abundance variations among the observed population. The methods for achieving the IMF from the observed distribution are most thoroughly outlined by Miller and Scalo but can be stated briefly, since they also relate to an accurate testing of various proposed stochastic methods. It should first be noted that the problems encountered for stellar distributions are quite similar to those with which studies of galaxies and thdr intrinsic properties have to deal. 

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