University of Surrey

Test tubes in the lab Research in the ATI Dance Research

THE MASSES OF LOCAL GROUP DWARF SPHEROIDAL GALAXIES: THE DEATH OF THE UNIVERSAL MASS PROFILE

Collins, MLM, Chapman, SC, Rich, RM, Ibata, RA, Martin, NF, Irwin, MJ, Bate, NF, Lewis, GF, Penarrubia, J, Arimoto, N, Casey, CM, Ferguson, AMN, Koch, A, McConnachie, AW and Tanvir, N (2014) THE MASSES OF LOCAL GROUP DWARF SPHEROIDAL GALAXIES: THE DEATH OF THE UNIVERSAL MASS PROFILE The Astrophysical Journal, 783 (7).

[img] Text
Masses_local_group_01.pdf - Version of Record
Restricted to Repository staff only
Available under License : See the attached licence file.

Download (2MB)
[img]
Preview
Text (licence)
SRI_deposit_agreement.pdf
Available under License : See the attached licence file.

Download (33kB) | Preview

Abstract

We investigate the claim that all dwarf spheroidal galaxies (dSphs) reside within halos that share a common, universal mass profile as has been derived for dSphs of the galaxy. By folding in kinematic information for 25 Andromeda dSphs, more than doubling the previous sample size, we find that a singular mass profile cannot be found to fit all of the observations well. Further, the best-fit dark matter density profile measured solely for the Milky Way dSphs is marginally discrepant with that of the Andromeda dSphs (at just beyond the 1σ level), where a profile with lower maximum circular velocity, and hence mass, is preferred. The agreement is significantly better when three extreme Andromeda outliers, And XIX, XXI, and XXV, all of which have large half-light radii (600 pc) and low-velocity dispersions (σv < 5 km s−1), are omitted from the sample. We argue that the unusual properties of these outliers are likely caused by tidal interactions with the host galaxy.

Item Type: Article
Subjects : Physics
Divisions : Faculty of Engineering and Physical Sciences > Physics
Authors :
AuthorsEmailORCID
Collins, MLMUNSPECIFIEDUNSPECIFIED
Chapman, SCUNSPECIFIEDUNSPECIFIED
Rich, RMUNSPECIFIEDUNSPECIFIED
Ibata, RAUNSPECIFIEDUNSPECIFIED
Martin, NFUNSPECIFIEDUNSPECIFIED
Irwin, MJUNSPECIFIEDUNSPECIFIED
Bate, NFUNSPECIFIEDUNSPECIFIED
Lewis, GFUNSPECIFIEDUNSPECIFIED
Penarrubia, JUNSPECIFIEDUNSPECIFIED
Arimoto, NUNSPECIFIEDUNSPECIFIED
Casey, CMUNSPECIFIEDUNSPECIFIED
Ferguson, AMNUNSPECIFIEDUNSPECIFIED
Koch, AUNSPECIFIEDUNSPECIFIED
McConnachie, AWUNSPECIFIEDUNSPECIFIED
Tanvir, NUNSPECIFIEDUNSPECIFIED
Date : 1 March 2014
Identification Number : 10.1088/0004-637X/783/1/7
Copyright Disclaimer : Copyright 2014. The American Astronomical Society. All rights reserved
Uncontrolled Keywords : dark matter – galaxies: dwarf – galaxies: fundamental parameters – galaxies: kinematics and dynamics – Local Group
Depositing User : Symplectic Elements
Date Deposited : 03 Aug 2016 14:01
Last Modified : 03 Aug 2016 14:01
URI: http://epubs.surrey.ac.uk/id/eprint/811375

Actions (login required)

View Item View Item

Downloads

Downloads per month over past year


Information about this web site

© The University of Surrey, Guildford, Surrey, GU2 7XH, United Kingdom.
+44 (0)1483 300800