Dust-to-gas ratio and star formation history of blue compact dwarf galaxies

Abstract

Abstract. This paper investigates the origin of the observed large variety in dust-to-gas ratio, D, among blue compact dwarf galaxies (BCDs). By applying our chemical evolution model, we find that the dust destruction can largely suppress the dust-to-gas ratio when the metallicity of a BCD reaches 12 + log (O/H) ∼ 8, i.e., a typical metallicity level of BCDs. We also show that dust-to-gas ratio is largely varied owing to the change of dust destruction efficiency that has two effects: (i) a significant contribution of Type Ia supernovae to total supernova rate; (ii) variation of gas mass contained in a star-forming region. While mass loss from BCDs was previously thought to be the major cause for the variance of D, we suggest that the other two effects are also important. We finally discuss the intermittent star formation history, which naturally explains the large dispersion of dust-to-gas ratio among BCDs.

Dust Content of Virgo Star-Forming Dwarf Galaxies

“…Also illustrated are data from the literature [13,14,20]. Selected model predictions for the D vs metallicity relation are also shown [3,11]. Our estimates of D for the three dwarfs, based on the single-temperature fit to the data, are roughly consistent with the predictions of dust formation models from [3].…”

TheHerschelVirgo Cluster Survey

“…The ratio D is known to correlate with the oxygen abundance (Lisenfeld & Ferrara 1998;Edmunds 2001;Hirashita et al 2002;James et al 2002). Here we check whether the gas and dust masses we obtained for these galaxies in the Virgo cluster are compatible with the predictions of dust formation models.…”

“…The dust-to-gas-mass ratio D (M dust /M gas ) not only provides information about the amount of metals that are locked in dust grains, but also provides an indication of the star-formation history of a galaxy, reflecting the net balance between the formation and destruction of dust (Hirashita et al 2002). The ratio D is known to correlate with the oxygen abundance (Lisenfeld & Ferrara 1998;Edmunds 2001;Hirashita et al 2002;James et al 2002).…”

Star Forming Dwarf Galaxies

“…The sample has been collected from various publications [4,13,37,50,63,95,129,137,161,Bergvall et al,unpublished]. The classification is therefore not homogeneous and the sample is not in any sense complete.…”