The Early Chemical Evolution of Dwarf Irregular Galaxies

Author(s)

Gerhard Hensler, Simone Recchi, Joachim Köppen, Andreas Rieschick

Abstract

Testing theoretical yields stemming from stars of different masses and therefore different lifetimes the early phases of galaxy evolution can provide fundamental insights into the early metal enrichment of the interstellar medium (ISM). In particular mixing processes between the different gas phases can be recognized by the analyses of the easily accessible elements oxygen and nitrogen (or carbon) which on the other hand are nucleosythesized in stellar progenitors of different masses and

deposited into different phases of the ISM according to the connected energy release. In addition gas infall and outflow affect ratios and absolute abundances of these tracer elements. For damped-Lyman alpha systems it is generally accepted that we catch the nursery of more massive galaxies during their disk formation and our understanding of the observed N/O-O relations has recently profitted from better observations and improved theoretical yields. Since dwarf irregular galaxies (dIrrs) evolve in lower gravitational potentials internal or external energetic processes such as galactic winds and gas infall are expected to have larger influences on the chemical evolution. By means of chemodynamical models this early evolution of dIrrs is followed and will be discussed in the context of observations and theoretical evolutionary paths within the N/O-O metallicities.

Organisation(s)

Department of Astrophysics

External organisation(s)

Université de Strasbourg

Pages

554-559

Publication date

2005

Austrian Fields of Science 2012

1030 Physics, Astronomy

Portal url

https://ucrisportal.univie.ac.at/en/publications/107b160d-38ff-4b29-9946-ae57473838f0