Query : 2002A&A...384..799R

2002A&A...384..799R - Astronomy and Astrophysics, volume 384, 799-811 (2002/3-4)

Multiple starbursts in Blue Compact Galaxies.


Abstract (from CDS):

In this paper we present some results concerning the effects of two instantaneous starbursts, separated by a quiescent period, on the dynamical and chemical evolution of Blue Compact Dwarf galaxies. In particular, we compare the model results to the galaxy IZw18, which is a very metal-poor, gas-rich dwarf galaxy, possibly experiencing its first or second burst of star formation. We follow the evolution of a first weak burst of star formation followed by a second more intense one occurring after several hundred million years. We find that a galactic wind develops only during the second burst and that metals produced in the burst are preferentially lost, relative to the hydrogen gas. We predict the evolution of several chemical abundances (H, He, C, N, O, α-elements, Fe) in the gas inside and outside the galaxy, by taking into account, in detail, the chemical and energetical contributions from type II and Ia supernovae. We find that the abundances predicted for the star forming region are in good agreement with the HII region abundances derived for IZw18. We also predict the abundances of C, N and O expected for the HI gas to be compared with future FUSE abundance determinations. We conclude that IZw18 must have experienced two bursts of star formation, one occurred ∼300Myr ago and a recent one with an age between 4-7Myr. However, by taking into account also other independent estimates, such as the color-magnitude diagram and the spectral energy distribution of stars in IZw18, and the fact that real starbursts are not instantaneous, we suggest that it is more likely that the burst age is between 4 and 15Myr.

Abstract Copyright:

Journal keyword(s): galaxies: evolution - hydrodynamics - ISM: abundances - ISM: bubbles

Simbad objects: 3

goto Full paper

goto View the references in ADS

Number of rows : 3
N Identifier Otype ICRS (J2000)
ICRS (J2000)
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2021
1 SBSG 0335-052 bCG 03 37 44.04 -05 02 38.5     16.65     ~ 443 1
2 LEDA 2790884 bCG 08 25 55.521 +35 32 31.96   18.2       ~ 107 1
3 Mrk 116 PaG 09 34 02.1 +55 14 25           ~ 1025 1

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2002A&A...384..799R and select 'bookmark this link' or equivalent in the popup menu


© Université de Strasbourg/CNRS

    • Contact