The impact of binary star yields on the spectra of galaxies

TL;DR

This study investigates how binary star yields influence the spectral features of galaxies, revealing small but potentially significant effects on chemical signatures and spectral lines, especially from different SNeIa progenitor models.

Contribution

The paper introduces a galactic chemical evolution model that incorporates binary star yields beyond SNeIa, highlighting their impact on galaxy spectra and chemical signatures.

Findings

Binary yields cause small systematic effects within observational uncertainties.

Different SNeIa progenitor models significantly affect spectral line strengths.

Binary star effects are less prominent than SNeIa variations but still relevant.

Abstract

One of the complexities in modelling integrated spectra of stellar populations is the effect of interacting binary stars besides type Ia supernovae (SNeIa). These include common envelope systems, CVs, novae, and are usually ignored in models predicting the chemistry and spectral absorption line strengths in galaxies. In this paper predictions of chemical yields from populations of single and binary stars are incorporated into a galactic chemical evolution model to explore the significance of the effects of these other binary yields. Effects on spectral line strengths from different progenitor channels of SNeIa are also explored. Small systematic effects are found when the yields from binaries, other than SNeIa, are included, for a given star formation history. These effects are, at present, within the observational uncertainties on the line strengths. More serious differences can arise in considering different types of SNIa models, their rates and contributions.