Star formation in the intragroup medium and other diagnostics of the evolutionary stages of compact groups of galaxies - Astrophysics > Cosmology and Nongalactic AstrophysicsReport as inadecuate




Star formation in the intragroup medium and other diagnostics of the evolutionary stages of compact groups of galaxies - Astrophysics > Cosmology and Nongalactic Astrophysics - Download this document for free, or read online. Document in PDF available to download.

Abstract: Context: Compact groups of galaxies are entities that have high densities ofgalaxies and serve as laboratories to study galaxy interactions, intergalacticstar formation and galaxy evolution.Aims: The main goal of this study is to search for young objects in theintragroup medium of seven compact groups of galaxies: HCG 2, 7, 22, 23, 92,100 and NGC 92 as well as to evaluate the stage of interaction of each group.Methods: We used Fabry-Perot velocity fields and rotation curves togetherwith GALEX NUV and FUV images and optical R-band and HI maps.Results: i HCG 7 and HCG 23 are in early stages of interaction, ii HCG 2and HCG 22 are mildly interacting, and iii HCG 92, HCG 100 and NGC 92 are inlate stages of evolution. We find that all three evolved groups containpopulations of young blue objects in the intragroup medium, consistent withages < 100 Myr, of which several are younger than < 10 Myr. We also report thediscovery of a tidal dwarf galaxy candidate in the tail of NGC 92. These threegroups, besides containing galaxies that have peculiar velocity fields, alsoshow extended HI tails.Conclusions: Our results indicate that the advanced stage of evolution of agroup, together with the presence of intragroup HI clouds, may lead to starformation in the intragroup medium. A table containing all intergalactic HIIregions and tidal dwarf galaxies confirmed to date is appended.



Author: S. Torres-Flores, C. Mendes de Oliveira, D. F. de Mello, P. Amram, H. Plana, B. Epinat, J. Iglesias-Paramo

Source: https://arxiv.org/







Related documents