The chemical evolution of IC10
  Dwarf irregular galaxies are relatively simple unevolved objects where it is
easy to test models of galactic chemical evolution. We attempt to determine the
star formation and gas accretion history of IC10, a local dwarf irregular for
which abundance, gas, and mass determinations are available. We apply detailed
chemical evolution models to predict the evolution of several chemical elements
(He, O, N, S) and compared our predictions with the observational data. We
consider additional constraints such as the present-time gas fraction, the star
formation rate (SFR), and the total estimated mass of IC10. We assume a dark
matter halo for this galaxy and study the development of a galactic wind. We
consider different star formation regimes: bursting and continuous. We explore
different wind situations: i) normal wind, where all the gas is lost at the
same rate and ii) metal-enhanced wind, where metals produced by supernovae are
preferentially lost. We study a case without wind. We vary the star formation
efficiency (SFE), the wind efficiency, and the time scale of the gas infall,
which are the most important parameters in our models. We find that only models
with metal-enhanced galactic winds can reproduce the properties of IC10. The
star formation must have proceeded in bursts rather than continuously and the
bursts must have been less numerous than ~10 over the whole galactic lifetime.
Finally, IC10 must have formed by a slow process of gas accretion with a
timescale of the order of 8 Gyr.
