The Herschel Virgo Cluster Survey. V. Star-forming dwarf galaxies - dust in metal-poor environments

We present the dust properties of a small sample of Virgo cluster dwarf galaxies drawn from the science demonstration phase data set of the Herschel Virgo Cluster Survey. These galaxies have low metallicities (7.8 < 12 + log(O/H) < 8.3) and star-formation rates ≲10^-1 M_⊙ yr^-1. We measure the spectral energy distribution (SED) from 100 to 500 μm and derive dust temperatures and dust masses. The SEDs are fitted by a cool component of temperature T ≲ 20 K, implying dust masses around 10⁵ M_⊙ and dust-to-gas ratios D within the range 10^-3-10^-2. The completion of the full survey will yield a larger set of galaxies, which will provide more stringent constraints on the dust content of star-forming dwarf galaxies.

Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.