We investigate how explosions of aspherical supernovae (A-SNe) can influence star formation histories and chemical evolution of dwarf galaxies by using a new chemodynamical model. We mainly present the numerical results of two comparative models so that the A-SN feedback effects on galaxies can be more clearly seen. SNe originating from stars with masses larger than 30M⊙ are A-SNe in the 'ASN' model, whereas all SNe are spherical ones (S-SNe) in the 'SSN' model. Each S-SN and A-SN are assumed to release feedback energy of 1051 and 1052 erg, respectively, and chemical yields and feedback energy of A-SN ejecta depend on angles between the axis of symmetry and the ejection directions. We find that star formation can become at least by a factor of ~3 lower in the ASN model in comparison with the SSN one owing to the more energetic feedback of A-SNe. As a result of this, chemical evolution can proceed very slowly in the ASN model. A-SN feedback effects can play a significant role in the formation of giant gaseous holes and energetic gaseous outflow and unique chemical abundances (e.g. high [Mg/Ca]). Based on these results, we provide a number of implications of the A-SN feedback effects on galaxy formation and evolution. © 2012 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.
|Journal||Monthly Notices of the Royal Astronomical Society: Letters|
|Publication status||Published - 2013|