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Register a new userH-ATLAS: The Far-Infrared properties of galaxies in and around the Coma Cluster
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Jonathan Davies Prof.
Publication date
2016
fields
Physics
and research's language is
English
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We describe a far infrared survey of the Coma cluster and the galaxy filament it resides within. Our survey covers an area of $sim$150 deg$^2$ observed by $Herschel$ H-ATLAS in five bands at 100, 160, 250, 350 and 500$mu$m. The SDSS spectroscopic survey ($m_{r} le 17.8)$ is used to define an area (within the Virial radius) and redshift selected ($4268 < v < 9700$ km s$^{-1}$) sample of 744 Coma cluster galaxies - the Coma Cluster Catalogue (CCC). For comparison we also define a sample of 951 galaxies in the connecting filament - the Coma Filament Catalogue (CFC). The optical positions and parameters are used to define appropriate apertures to measure each galaxys far infrared emission. We have detected 99 of 744 (13%) and 422 of 951 (44%) of the cluster and filament galaxies in the SPIRE 250$mu$m band. We consider the relative detection rates of galaxies of different morphological types finding that it is only the S0/Sa population that shows clear differences between the cluster and filament. We find no differences between the dust masses and temperatures of cluster and filament galaxies with the exception of early type galaxy dust temperatures, which are significantly hotter in the cluster than in the filament (X-ray heating?). From a chemical evolution model we find no evidence for different evolutionary processes (gas loss or infall) between galaxies in the cluster and filament.
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