Type Ia Supernovae The Chemical Output Of The Stellar Population

Nowadays, the chemical evolution of galaxies is a very hot topic in astrophysics field. Considerable progress have been attained in this field in the past, and a lot of phenomena have been explained. However, there still exist many problems. It is widely accepted that stellar populations are the building blocks of galaxies and SNe Ia are dominant contributors to Fe element which is crucial to the chemical evolution of galaxies. In the current chemical evolution models (CEMs) of galaxies, the treatment of SNe Ia is oversimplified. They only include the SNe Ia rate as a free parameter in order to reproduce some observational constraints, without modelling in detail the evolution of the progenitor systems. This may lead to some uncertainties in the results of CEMs. In this thesis, we have studied the influence of SNe Ia on the chemical yields of stellar populations. We have used two popular progenitor scenarios for SNe Ia (i.e. the SD scenario and the DD scenario) to obtain the rates of SNe Ia for different metallicities, respectively. For comparison, we also calculate the rate of SNe Ia by the way that was commonly adopted in CEMs. We found that the SNe Ia commonly used in CEMs are very different from that calculated by the binary populations in the rate, in the delayed timescale and in the span time. Finally, we applied these rates of SNe Ia to the chemical yields of stellar populations, and found that the influence of SNe Ia on the C, N, O and Mg elements is insignificant, but the influence of SNe Ia on the Fe enrichment and on the [Mg/Fe] evolution is significant. Different treatments of SNe Ia lead to different Fe enrichment and different [Mg/Fe] evolution, this probably suggests that there exist some uncertainties in the current CEMs.