DustPedia: the relationships between stars, gas, and dust for galaxies residing in different environments

Abstract

We use a sub-set of the DustPedia galaxy sample (461 galaxies) to investigate the effect the environment has had on galaxies. We consider Virgo cluster and field samples and also assign a density contrast parameter to each galaxy, as defined by the local density of SDSS galaxies. We consider their chemical evolution (using M<SUB>Dust</SUB>/M<SUB>Baryon</SUB> and M<SUB>Gas</SUB>/M<SUB>Baryon</SUB>), their specific star formation rate (SFR/M<SUB>Stars</SUB>), star formation efficiency (SFR/M<SUB>Gas</SUB>), stars-to-dust mass ratio (M<SUB>Stars</SUB>/M<SUB>Dust</SUB>), gas-to-dust mass ratio (M<SUB>Gas</SUB>/M<SUB>Dust</SUB>) and the relationship between star formation rate per unit mass of dust and dust temperature (SFR/M<SUB>Dust</SUB> and T<SUB>Dust</SUB>). Late type galaxies (later than Sc) in all of the environments can be modelled using simple closed box chemical evolution and a simple star formation history (SFR(t) ∝ t exp-t/τ). For earlier type galaxies the physical mechanisms that give rise to their properties are clearly much more varied and require a more complicated model (mergers, gas in or outflow). However, we find little or no difference in the properties of galaxies of the same morphological type within the cluster, field or with different density contrasts. It appears that it is morphology, how and whenever this is laid down, and consistent internal physical processes that primarily determine the derived properties of galaxies in the DustPedia sample and not processes related to differences in the local environment.