Submillimetre Observations of Clusters of Galaxies
Date Submitted
2017-04-21 15:16:39
HighRed
Ryan Cheale
University of Hertfordshire
Poster
James Geach (University of Hertfordshire), Alastair Edge (Durham University)
The SCUBA-2 Cluster Snapshot Survey (S2CSS) surveyed approximately 200 cluster regions from the MAssive Cluster survey (MACs). This was aimed at detecting bright gravitationally lensed submillimeter galaxies in short integration times at z = 0.3-0.6 in poor submillimeter conditions i.e. more than 1.7mm PWV (Band 3 and higher). A sample of seven 5-sigma 850um comprised of four gravitationally lensed sources and three were strong submillimeter emission originates from the central Bright Cluster Galaxy. Two of the lenses were previously known but now have 850-um flux densities attributed to them. One source is an exceptionally lensed in the MACSJ0600.1-2008 field with a peak 850-um flux density of S_850um = 125 +- 7 mJy.
Not all clusters contain a significant submillimeter excess, however, by matching maps to the NVSS 1.4-GHz survey and stacking the S2CSS maps into bins of radio flux, it revealed a large average submillimeter excess present in a radio loud BCGs (11-mJy); linking a submillimeter emission component to radio loud systems. Comparing the well-known target positions from the MAC survey with the 1.4-GHz NVSS and TGSS-ADR 150-MHz surveys it has also been possible to construct SEDs of 1.4-GHz binned stacks of the matched 850um maps. This has revealed an average dust emission component co-located with the brightest cluster galaxies across all bins, which may provide a reliable estimation to the submillimeter emission of clusters and potentially indicate on-going star formation or a dominate synchrotron emission component present.