Physical properties of 6dF dwarf galaxies

TL;DR

This study applies spectral synthesis to 6dF dwarf galaxies to derive their stellar population properties, providing a valuable database and demonstrating consistency with SDSS results while reducing aperture effects.

Contribution

It introduces a comprehensive analysis of 6dF dwarf galaxies using spectral synthesis, expanding the understanding of their physical properties with reduced aperture bias.

Findings

Good agreement with SDSS-based studies

Reduced aperture effects due to larger fiber size

Database of physical properties and emission spectra created

Abstract

Spectral synthesis is basically the decomposition of an observed spectrum in terms of the superposition of a base of simple stellar populations of various ages and metallicities, producing as output the star formation and chemical histories of a galaxy, its extinction and velocity dispersion. The STARLIGHT code provides one of the most powerful spectral synthesis tools presently available. We have applied this code to the entire Six-Degree-Field Survey (6dF) sample of nearby star-forming galaxies, selecting dwarf galaxy candidates with the goal of: (1) deriving the age and metallicity of their stellar populations and (2) creating a database with the physical properties of our sample galaxies together with the FITS files of pure emission line spectra (i.e. the observed spectra after subtraction of the best-fitting synthetic stellar spectrum). Our results yield a good qualitative and quantitative agreement with previous studies based on the Sloan Digital Sky Survey (SDSS). However, an advantage of 6dF spectra is that they are taken within a twice as large fiber aperture, much reducing aperture effects in studies of nearby dwarf galaxies.