Publication details for Dr Nigel MetcalfeBate, N. F., McMonigal, B., Lewis, G. F., Irwin, M. J., Gonzalez-Solares, E., Shanks, T. & Metcalfe, N. (2015). The shell game: a panoramic view of Fornax. Monthly Notices of the Royal Astronomical Society 453(1): 690-703.
- Publication type: Journal Article
- ISSN/ISBN: 0035-8711 (print), 1365-2966 (online)
- DOI: 10.1093/mnras/stv1684
- Keywords: Galaxies: dwarf, Galaxies: individual: Fornax dSph, Local Group, Galaxies: stellar content.
- Further publication details on publisher web site
- Durham Research Online (DRO) - may include full text
Author(s) from Durham
We present a panoramic study of the Fornax dwarf spheroidal galaxy, using data obtained as part of the VLT Survey Telescope (VST) ATLAS Survey. The data presented here – a subset of the full survey – uniformly cover a region of 25 deg2 centred on the galaxy, in g, r and i bands. This large area coverage reveals two key differences to previous studies of Fornax. First, data extending beyond the nominal tidal radius of the dwarf highlight the presence of a second distinct red giant branch population. This bluer red giant branch appears to be co-eval with the horizontal branch population. Secondly, a shell structure located approximately 1 ∘ .
4 from the centre of Fornax is shown to be a mis-identified background overdensity of galaxies. This last result casts further doubt on the hypothesis that Fornax underwent a gas-rich merger in its relatively recent past.