Binary Stellar Population Synthesis Model

TL;DR

This paper develops a binary stellar population synthesis model that incorporates binary interactions, affecting the spectral properties and derived parameters of stellar populations, useful for galaxy survey analysis.

Contribution

It introduces a comprehensive EPS model including binary interactions and provides spectral data at various resolutions for galaxy studies.

Findings

Binary interactions make populations appear bluer.

Inclusion of interactions increases estimated age and metallicity.

Provides spectral data compatible with observational surveys.

Abstract

Using Yunnan evolutionary population synthesis (EPS) models, we present integrated colours, integrated spectral energy distributions (ISEDs) and absorption-line indices defined by the Lick Observatory image dissector scanner (Lick/IDS) system, for an extensive set of instantaneous-burst binary stellar populations (BSPs) with interactions. By comparing the results for populations with and without interactions we show that the inclusion of binary interactions makes the appearance of the population substantially bluer. This effect raises the derived age and metallicity of the population. To be used in the studies of modern spectroscopic galaxy surveys at intermediate/high spectral resolution, we also present intermediate- (3A) and high-resolution (~0.3A) ISEDs and Lick/IDS absorption-line indices for BSPs. To directly compare with observations the Lick/IDS absorption indices are also presented by measuring them directly from the ISEDs.