Dust Emission in Early-Type Galaxies with the Herschel Virgo Cluster
  Survey
  We have searched for dust in an optical sample of 910 Early-Type Galaxies
(ETG) in the Virgo cluster (447 of which are optically complete at m_pg <=
18.0), extending also to the dwarf ETG, using Herschel images at 100, 160, 250,
350 and 500 microns. Dust was found in 52 ETG (46 are in the optically complete
sample), including M87 and another 3 ETG with strong synchrotron emisssion.
Dust is detected in 17% of ellipticals, 41% of lenticulars, and in about 4% of
dwarf ETG. The dust-to-stars mass ratio increases with decreasing optical
luminosity, and for some dwarf ETG reaches values similar to those of the dusty
late-type galaxies. Slowly rotating ETG are more likely to contain dust than
fast rotating ones. Only 8 ETG have both dust and HI, while 39 have only dust
and 8 have only HI, surprisingly showing that only rarely dust and HI survive
together. ETG with dust appear to be concentrated in the densest regions of the
cluster, while those with HI tend to be at the periphery. ETG with an X-ray
active SMBH are more likely to have dust and vice versa the dusty ETG are more
likely to have an active SMBH.
