What will blue compact dwarf galaxies evolve into?

Abstract

We present and analyse the photometric properties of a nearly complete sample of blue compact dwarf (BCD) and irregular galaxies in the Virgo cluster from multi-band SDSS images. Our study intends to shed light on the ongoing debate of whether a structural evolution from present-day star-forming dwarf galaxies in a cluster environment into ordinary early-type dwarf galaxies is possible based on the structural properties. For this purpose, we decompose the surface brightness profiles of the BCDs into the luminosity contribution of the starburst component and that of their underlying low surface brightness (LSB) host. The latter dominates the stellar mass of the BCD. We find that the LSB-components of the Virgo BCDs are structurally compatible with the more compact half of the Virgo early-type dwarfs, except for a few extreme BCDs. Thus, after termination of starburst activity, the BCDs will presumably fade into galaxies that are structurally similar to ordinary early-type dwarfs. In contrast, the irregulars are more diffuse than the BCDs and are structurally similar to the more diffuse half of the Virgo early-type dwarfs. Therefore, the present-day Virgo irregulars are not simply non-starbursting BCDs. If starbursts in cluster BCDs are transient phenomena with a duration of ∼100 Myr or less, during which the galaxies could not travel more than ∼100 kpc, then a substantial number of non-starbursting counterparts of these systems must populate the same spatial volume, namely the Virgo cluster outskirts. The majority of them would have to be early-type dwarfs, based on the abundance of different galaxy types with similar colours and structural parameters to the LSB-components of the BCDs. However, most Virgo BCDs have redder LSB-host colours and a less prominent starburst than typical field BCDs, preventing a robust conclusion on possible oscillations between BCDs and early-type dwarfs.

Constraining the Stellar Populations and Star Formation Histories of Blue Compact Dwarf Galaxies with SED Fits

“…Many groups have studied or discussed the implications of a population of faded or post-burst BCDs (Sánchez Almeida et al 2008Amorín et al 2012;Lelli et al 2012;Koleva et al 2013;Janowiecki & Salzer 2014;Meyer et al 2014). Here it is important to separate possible evolutionary pathways based on whether external or internal effects are being considered.…”

On the occurrence of galaxy harassment

“…The sample consists of 864 members and possible members of the Virgo cluster, classified as dE, dEdi, S0, Sc, Sd, Sm, and Im galaxies based on the Virgo Cluster Catalogue (Binggeli et al 1985) down to the completeness limit of a B-band apparent magnitude 18 and with velocities below 3500 km s −1 . The measurements of r-band brightness, surface brightness, and half-light radius were taken from Lisker et al (2007), Janz & Lisker (2008), and Meyer et al (2014. The sample comprises 449 dE , 41 dEdi, 73 S0, 114 Sc/Sd, 26 Sm, and 161 Im galaxies.…”

“…Therefore, to describe the evolution of galaxies in A103, page 9 of 14 a cluster environment, one has to pay attention to the different possible orientations of the disk. Figure 10 shows the distribution of different galaxy types of the Virgo cluster (Lisker et al 2007;Janz & Lisker 2008Meyer et al 2014) and the distribution of our initial galaxy models (green), as well as their remnants (red) in the μ eff − r eff (top panel) and in the M r − μ eff (bottom panel) plane. The points for the initial and remnant galaxies are the mean values averaged over different projection angles (edge-on = 90…”

Studying star forming dwarf galaxies in Abell 779, Abell 1367, Coma, and Hercules clusters

“…Mateo 1998;Karachentsev et al 2013), BCDs are encountered mostly in denser environment and galaxy clusters and harbour starburst possibly triggered by strong environmental influences (e.g. Vilchez 1995;Meyer et al 2014). The physical and chemical properties of dIs and BCDs are linked, suggesting that BCDs represent the outcome of dIs or just some temporary stages of dIs encountered in outburst (e.g.…”