Stellar populations in local star-forming galaxies - I. Data and modelling procedure

We present an analysis of the integrated properties of the stellar populations in the Universidad Complutense de Madrid (UCM) Survey of Halpha-selected galaxies. In this paper, the first of a series, we describe in detail the techniques developed to model star-forming galaxies using a mixture of ste...

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Bibliographic Details
Authors: Pérez González, Pablo Guillermo, Gil De Paz, Armando, Zamorano Calvo, Jaime, Gallego Maestro, Jesús, Alonso Herrero, A., Aragón Salamanca, A,
Format: article
Publication Date:2003
Country:España
Institution:Universidad Complutense de Madrid (UCM)
Repository:Docta Complutense
Language:English
OAI Identifier:oai:docta.ucm.es:20.500.14352/51640
Online Access:https://hdl.handle.net/20.500.14352/51640
Access Level:Open access
Keyword:52
Emission-line galaxies
Compact dwarf galaxies
Initial mass function
Hubble deep field
Infrared standard stars
Alpha emitting galaxies
Formation rate density
Lyman-break galaxies
UCM list-I
Formation history
Astrofísica
Astronomía (Física)
Description
Summary:We present an analysis of the integrated properties of the stellar populations in the Universidad Complutense de Madrid (UCM) Survey of Halpha-selected galaxies. In this paper, the first of a series, we describe in detail the techniques developed to model star-forming galaxies using a mixture of stellar populations, and taking into account the observational uncertainties. We assume a recent burst of star formation superimposed on a more evolved population. The effects of the nebular continuum, line emission and dust attenuation are taken into account. We also test different model assumptions, including the choice of specific evolutionary synthesis model, initial mass function, star formation scenario and the treatment of dust extinction. Quantitative tests are applied to determine how well these models fit our multiwavelength observations for the UCM sample. Our observations span the optical and near-infrared, including both photometric and spectroscopic data. Our results indicate that extinction plays a key role in this kind of study, revealing that low- and high-obscured objects may require very different extinction laws and must be treated differently. We also demonstrate that the UCM Survey galaxies are best described by a short burst of star formation occurring within a quiescent galaxy, rather than by continuous star formation. A detailed discussion on the inferred parameters, such as the age, burst strength, metallicity, star formation rate, extinction and total stellar mass for individual objects, is presented in Paper II of this series.