Volume 422, Number 1, July IV 2004
|Page(s)||55 - 64|
|Published online||06 July 2004|
Periodic bursts of star formation in irregular galaxies
Leiden Observatory, Leiden University, PO Box 9513, 2300 RA Leiden, The Netherlands
Corresponding author: F. I. Pelupessy, email@example.com
Accepted: 24 March 2004
We present N-body/SPH simulations of the evolution of an isolated dwarf galaxy including a detailed model for the ISM, star formation and stellar feedback. Depending on the strength of the feedback, the modelled dwarf galaxy shows periodic or quasi-periodic bursts of star formation of moderate strength. The period of the variation is related to the dynamical timescale, of the order of 1.5 108 yr. We show that the results of these simulations are in good agreement with recent detailed observations of dwarf irregulars (dIrr) and that the peculiar kinematic and morphological properties of these objects, as revealed by high resolution HI studies, are fully reproduced. We discuss these results in the context of recent surveys of dwarf galaxies and point out that if the star formation pattern of our model galaxy is typical of dwarf irregulars this could explain the scatter of observed properties of dwarf galaxies. Specifically, we show that the time-sampled distribution of the ratio between the instanteneous star formation rate (SFR) and the mean SFR is similar to the distribution in observed samples of dwarf galaxies.
Key words: methods: numerical / methods: N-body simulations / galaxies: dwarf / Galaxy: evolution / galaxies: ISM / galaxies: irregular
© ESO, 2004
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.