The Environment of Star-Forming Dwarf Galaxies

Noeske, K. G.; Iglesias-Páramo, J.; Vílchez, J. M.; Fricke, K. J.
Bibliographical reference

Astrophysics and Space Science, v. 276, Issue 2/4, p. 577-583 (2001).

Advertised on:
3
2001
Number of authors
4
IAC number of authors
2
Citations
0
Refereed citations
0
Description
We are currently performing a new analysis of the close environment of star-forming dwarf galaxies and its effects on their star-forming activity. For a sample of 142 thoroughly studied objects, we search the NASA Extragalactic Database for possible companion galaxies of any apparent luminosity and angular size. From a first analysis of a part of our sample, we find only about 50% of our objects to be isolated in the sense that no companion object was detected within a redshift difference of 500 km s^-1 and an angular separation corresponding to a projected distance of 1 Mpc, assuming H_0=75 km s^-1 Mpc^-1. By splitting the sample into different redshift intervals, we demonstrate an observational bias against low-luminosity companion objects which implies that a large fraction of star-forming dwarf galaxies, although lacking bright companions, might possess dwarf companion objects. Similarly to other authors, we find no evidence for a difference in star-forming activity due to the presence or absence of possible companions.