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Ohh my! 158 new dwarf galaxies discovered using the DECam!

Well, for starters, the DECam is the Camera on the 4-metre Blanco telescope at the CTIO (Cerro-Tololo Inter-american Observatory). It was originally designed for the DES (Dark Energy Survey) but I guess it's also being used for other astronomical observations. The authors are part of the NGFS (Next Generation Fornax Survey) efforts at the CTIO.

Coming to the paper (found here), the authors give a preliminary report of the 158 new dwarf galaxies they've discovered in the Fornax cluster central regions. There is a lot more science to come out of the data but a preliminary analysis shows that the dwarf galaxies seem to be clustered within the Fornax cluster core, clustering previous predicted in simulations. The authors also fit the surface brightness distribution for each of the dwarf galaxies found to estimate their effective radii. The dwarfs found seem to be fainter and smaller than similar ones (referred to as Ultra Diffuse Galaxies - UDGs) found in the Virgo cluster and the Coma cluster surveys. Depending on the fits, the authors are also able to differentiate the UDGs as nucleated and non-nucleated, and they also investigated the correlation between nucleation fraction with galaxy luminosity.

Again, I need to look up if there are radio surveys of the Fornax clusters and if there are radio counterparts known for these newly discovered UDGs. If not, that would be another interesting set of observations, data that would again help understanding the evolution of low-mass galaxies. The upcoming set of papers by this team are ones to watch out for.

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