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Metallicity distribution function Galaxy

The metallicity distribution function (MDF) in galaxy halos contains other important clues about the process of galaxy formation. In recent years, a wealth of MDF data have been collected for the Milky Way (eg. [3], [4]), M3I (eg. [I]),... [Pg.264]

Thus the mass of stars and that of the whole system steadily increase while z soon approaches 1 and the stellar metallicity distribution is very narrow (see Fig. 8.24). The accretion rate is constant in time if the star formation rate is any fixed function of the mass of gas. Other models in which the accretion rate is constant, but less than in the extreme model, have been quite often considered in the older literature (e.g. Twarog 1980), but are less popular now because they are not well motivated from a dynamical point of view, there is an upper limit to the present inflow rate into the whole Galaxy of about 1 M0yr 1 from X-ray data (Cox Smith 1976) and they do not provide a very good fit to the observed metallicity distribution function. [Pg.277]

More general model for the mass of the galaxy and the distribution of mass between stars and gas as a function of time. This model includes infall of metal-poor gas onto the galactic disk, sequestration of gas in stellar remnants, and return of newly synthesized elements from stars. The mass of gas is constrained to match the currently observed value of -10%. [Pg.310]

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. [Pg.497]


See other pages where Metallicity distribution function Galaxy is mentioned: [Pg.251]    [Pg.276]    [Pg.246]    [Pg.383]    [Pg.303]    [Pg.365]    [Pg.73]    [Pg.247]    [Pg.17]    [Pg.171]   


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