Wide Field Views of M31's dE Satellites: NGC 147 and NGC 185

N. E. D. Noel, A. M. N. Ferguson, M. J. Irwin

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Panoramic imaging studies of the M31 halo are revealing a wealth of previously-unknown faint tidal debris [e.g. 1] suggesting that it presents a hostile environment for dwarf galaxies to live in. NGC 185 (MV=-15.6) and NGC 147 (MV=-15.1) are dwarf elliptical (dE) satellites of M31 which currently reside in the remote outer halo (R-M31 similar to 160 kpc). Given their similarity to more distant, unresolved, dEs, NGC 147 and NGC 185 are ideal workplaces to carry out detailed studies in dEs. While NGC 147 and 185 have been studied extensively in the past, almost all previous studies have been of small field-of-view. Our ongoing wide-field analysis will allow a thorough examination of the global content and structure of these systems and enable us to assess the extent to which they have previously interacted with M31 as well as each other. We present first results from our ongoing analysis of wide-field near-IR and optical imagery of these systems which we are using to derive the first truly global views of their overall structures and stellar contents. In particular, UKIRT/WFCAM JHK data are used to identify and analyse luminous asymptotic giant branch (AGB) stars in NGC 147 and NGC 185 and separate out C-rich and O-rich populations while INT/WFC Vi data are used to analyse the red giant branch (RGB) populations.

Original languageEnglish
Title of host publicationHUNTING FOR THE DARK: THE HIDDEN SIDE OF GALAXY FORMATION
EditorsVP Debattista, CC Popescu
Place of PublicationMELVILLE
PublisherAmerican Institute of Physics
Pages417-418
Number of pages2
ISBN (Print)978-0-7354-0786-2
Publication statusPublished - 2010
EventInternational Conference on Hunting for the Dark: The Hidden Side of Galaxy Formation - Qawra
Duration: 19 Oct 200923 Oct 2009

Conference

ConferenceInternational Conference on Hunting for the Dark: The Hidden Side of Galaxy Formation
CityQawra
Period19/10/0923/10/09

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