Skip to main content

Research Repository

Advanced Search

Tidal features of classical Milky Way satellites in a Λ cold dark matter universe

Wang, M.-Y.; Fattahi, A.; Cooper, A.P.; Sawala, T.; Strigari, L.E.; Frenk, C.S.; Navarro, J.F.; Oman, K.; Schaller, M.

Tidal features of classical Milky Way satellites in a Λ cold dark matter universe Thumbnail


M.-Y. Wang

A. Fattahi

A.P. Cooper

T. Sawala

L.E. Strigari

J.F. Navarro

K. Oman

M. Schaller


We use the APOSTLE (A Project Of Simulating The Local Environment) cosmological hydrodynamic simulations to examine the effects of tidal stripping on cold dark matter subhaloes that host three of the most luminous Milky Way dwarf satellite galaxies: Fornax, Sculptor and Leo I. We identify simulated satellites that match the observed spatial and kinematic distributions of stars in these galaxies, and track their evolution after infall. We find ∼30 per cent of subhaloes hosting satellites with present-day stellar mass 106–108 M⊙ experience >20 per cent stellar mass-loss after infall. Fornax analogues have earlier infall times compared to Sculptor and Leo I analogues. Star formation in Fornax analogues continues for ∼3–6 Gyr after infall, whereas Sculptor and Leo I analogues stop forming stars <2–3 Gyr after infall. Fornax analogues typically show more significant stellar mass-loss and exhibit stellar tidal tails, whereas Sculptor and Leo I analogues, which are more deeply embedded in their host dark matter haloes at infall, do not show substantial mass-loss due to tides. When additionally comparing the orbital motion of the host subaloes to the measured proper motion of Fornax, we find the matching more difficult; host subhaloes tend to have pericentres smaller than that measured for Fornax itself. From the kinematic and orbital data, we estimate that Fornax has lost 10–20 per cent of its infall stellar mass. Our best estimate for the surface brightness of a stellar tidal stream associated with Fornax is Σ ∼ 32.6 mag arcsec−2, which may be detectable with deep imaging surveys such as DES and LSST.


Wang, M., Fattahi, A., Cooper, A., Sawala, T., Strigari, L., Frenk, C., …Schaller, M. (2017). Tidal features of classical Milky Way satellites in a Λ cold dark matter universe. Monthly Notices of the Royal Astronomical Society, 468(4), 4887-4901.

Journal Article Type Article
Acceptance Date Mar 23, 2017
Online Publication Date Mar 25, 2017
Publication Date Jul 11, 2017
Deposit Date Jul 18, 2017
Publicly Available Date Jul 18, 2017
Journal Monthly Notices of the Royal Astronomical Society
Print ISSN 0035-8711
Electronic ISSN 1365-2966
Publisher Royal Astronomical Society
Peer Reviewed Peer Reviewed
Volume 468
Issue 4
Pages 4887-4901


Published Journal Article (6.9 Mb)

Copyright Statement
This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society © 2017. The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society.

You might also like

Downloadable Citations