Herschel photometry of brightest cluster galaxies in cooling flow clusters

Astronomy and Astrophysics (Impact Factor: 4.38). 05/2010; 518(4). DOI: 10.1051/0004-6361/201014572
Source: arXiv


The dust destruction timescales in the cores of clusters of galaxies are
relatively short given their high central gas densities. However, substantial
mid-infrared and sub-mm emission has been detected in many brightest cluster
galaxies. In this letter we present Herschel PACS and SPIRE photometry of the
brightest cluster galaxy in three strong cooling flow clusters, A1068, A2597
and Zw3146. This photometry indicates that a substantial mass of cold dust is
present (>3 x 10^7 Mo) at temperatures significantly lower (20-28K) than
previously thought based on limited MIR and/or sub-mm results. The mass and
temperature of the dust appear to match those of the cold gas traced by CO with
a gas-to-dust ratio of 80-120.

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