Service interruption on Monday 11 July from 12:30 to 13:00: all the sites of the CCSD (HAL, Epiciences, SciencesConf, AureHAL) will be inaccessible (network hardware connection).
Skip to Main content Skip to Navigation
Journal articles

A single-merger scenario for the formation of the giant stream and the warp of M31

Abstract : We propose that the accretion of a dwarf spheroidal galaxy provides a common origin for the giant southern stream and the warp of M31. We run about 40 full N-body simulations with live M31, infalling galaxies with varying masses and density profiles, and cosmologically plausible initial orbital parameters. Good agreement with a full range of observational data is obtained for a model in which a dark-matter-rich dwarf spheroidal, whose trajectory lies on the thin plane of corotating satellites of M31, is accreted from its turnaround radius of about 200 kpc into M31 at approximately 3 Gyr ago. The satellite is disrupted as it orbits in the potential well of the galaxy and forms the giant stream and in return heats and warps the disc of M31. We show that our cosmologically motivated model is favoured by the kinematic data over the empirical models in which the satellite starts its infall from a close distance of M31. Our model predicts that the remnant of the disrupted satellite resides in the region of the north-eastern shelf of M31. The results here suggest that the surviving satellites of M31 that orbit on the same thin plane, as the disrupted satellite once did, could have all been accreted from an intergalactic filament.
Document type :
Journal articles
Complete list of metadata
Contributor : Hal Sorbonne Université Gestionnaire Connect in order to contact the contributor
Submitted on : Sunday, April 24, 2022 - 4:18:25 PM
Last modification on : Thursday, May 12, 2022 - 6:22:03 PM


Publisher files allowed on an open archive



Raphael Sadoun, Roya Mohayaee, Jacques Colin. A single-merger scenario for the formation of the giant stream and the warp of M31. Monthly Notices of the Royal Astronomical Society, Oxford University Press (OUP): Policy P - Oxford Open Option A, 2014, 442, pp.160-175. ⟨10.1093/mnras/stu850⟩. ⟨insu-03645360⟩



Record views


Files downloads