Young accreted globular clusters in the outer halo of M31
-
Altmetric Citations
Mackey, Alasdair; Huxor, A; Ferguson, A. M. N.; Irwin, M. J.; Veljanoski, J.; McConnachie, Alan W; Ibata, Rodrigo A; Lewis, Geraint Francis; Tanvir, Nial R
Description
We report on observations of two newly discovered globular clusters in the outskirts of M31 made using the Gemini Multi-Object Spectrograph (GMOS) instrument on Gemini North. These objects, PAndAS-7 (PA-7) and PAndAS-8 (PA-8), lie at a galactocentric radius of 87 kpc and are projected, with separation 19 kpc, on to a field halo substructure known as the South-West Cloud. We measure radial velocities for the two clusters which confirm that they are almost certainly physically associated with...[Show more]
dc.contributor.author | Mackey, Alasdair | |
---|---|---|
dc.contributor.author | Huxor, A | |
dc.contributor.author | Ferguson, A. M. N. | |
dc.contributor.author | Irwin, M. J. | |
dc.contributor.author | Veljanoski, J. | |
dc.contributor.author | McConnachie, Alan W | |
dc.contributor.author | Ibata, Rodrigo A | |
dc.contributor.author | Lewis, Geraint Francis | |
dc.contributor.author | Tanvir, Nial R | |
dc.date.accessioned | 2015-12-13T22:16:29Z | |
dc.identifier.issn | 0035-8711 | |
dc.identifier.uri | http://hdl.handle.net/1885/70889 | |
dc.description.abstract | We report on observations of two newly discovered globular clusters in the outskirts of M31 made using the Gemini Multi-Object Spectrograph (GMOS) instrument on Gemini North. These objects, PAndAS-7 (PA-7) and PAndAS-8 (PA-8), lie at a galactocentric radius of 87 kpc and are projected, with separation 19 kpc, on to a field halo substructure known as the South-West Cloud. We measure radial velocities for the two clusters which confirm that they are almost certainly physically associated with this feature. Colour-magnitude diagrams reveal strikingly short, exclusively red horizontal branches in both PA-7 and PA-8; both also have photometric [Fe/H]=-1.35±0.15. At this metallicity, the morphology of the horizontal branch is maximally sensitive to age, and we use the distinctive configurations seen in PA-7 and PA-8 to demonstrate that both objects are very likely to be at least 2 Gyr younger than the oldest Milky Way globular clusters. Our observations provide strong evidence for young globular clusters being accreted into the remote outer regions of M31 in a manner entirely consistent with the established picture for the Milky Way, and add credence to the idea that similar processes play a central role in determining the composition of globular cluster systems in large spiral galaxies in general. | |
dc.publisher | Blackwell Publishing Ltd | |
dc.rights | Author/s retain copyright | |
dc.source | Monthly Notices of the Royal Astronomical Society | |
dc.subject | Keywords: General - galaxies; Globular clusters; Haloes - Local Group; Individual; M31 - galaxies | |
dc.title | Young accreted globular clusters in the outer halo of M31 | |
dc.type | Journal article | |
local.description.notes | Imported from ARIES | |
local.identifier.citationvolume | 429 | |
dc.date.issued | 2013 | |
local.identifier.absfor | 020100 - ASTRONOMICAL AND SPACE SCIENCES | |
local.identifier.ariespublication | f5625xPUB2456 | |
local.type.status | Published Version | |
local.contributor.affiliation | Mackey, Alasdair, College of Physical and Mathematical Sciences, ANU | |
local.contributor.affiliation | Huxor, A, Universität Heidelberg | |
local.contributor.affiliation | Ferguson, A. M. N., University of Edinburgh | |
local.contributor.affiliation | Irwin, M. J., University of Cambridge | |
local.contributor.affiliation | Veljanoski, J., University of Edinburgh | |
local.contributor.affiliation | McConnachie, Alan W, NRC Herzberg Institute of Astrophysics | |
local.contributor.affiliation | Ibata, Rodrigo A, Universite de Strasbourg | |
local.contributor.affiliation | Lewis, Geraint Francis, University of Sydney | |
local.contributor.affiliation | Tanvir, Nial R, University of Leicester | |
local.bibliographicCitation.issue | 1 | |
local.bibliographicCitation.startpage | 281 | |
local.bibliographicCitation.lastpage | 293 | |
local.identifier.doi | 10.1093/mnras/sts336 | |
dc.date.updated | 2016-02-24T08:58:37Z | |
local.identifier.scopusID | 2-s2.0-84874002209 | |
local.identifier.thomsonID | 000318238300045 | |
dcterms.accessRights | Open Access | |
Collections | ANU Research Publications |
Download
File | Description | Size | Format | Image |
---|---|---|---|---|
01_Mackey_Young_accreted_globular_2013.pdf | 1.41 MB | Adobe PDF |
Items in Open Research are protected by copyright, with all rights reserved, unless otherwise indicated.
Updated: 17 November 2022/ Responsible Officer: University Librarian/ Page Contact: Library Systems & Web Coordinator