The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here: https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

Oscar Agertz. Profile photo.

Oscar Agertz

Associate Professor / Senior university lecturer / Wallenberg Academy Fellow

Oscar Agertz. Profile photo.

VINTERGATAN-GM : How do mergers affect the satellite populations of MW-like galaxies?

Author

  • Gandhali D. Joshi
  • Andrew Pontzen
  • Oscar Agertz
  • Martin P. Rey
  • Justin Read
  • Florent Renaud

Summary, in English

We investigate the impact of a galaxy’s merger history on its system of satellites using the new VINTERGATAN-GM suite of zoom-in hydrodynamical simulations of Milky Way-mass systems. The suite simulates five realizations of the same halo with targeted ‘genetic modifications’ of a z ≈ 2 merger, but resulting in the same halo mass at z = 0. We find that differences in the satellite stellar mass functions last for 2.25−4.25 Gyr after the z ≈ 2 merger; specifically, the haloes that have undergone smaller mergers host up to 60 per cent more satellites than those of the larger merger scenarios. However, by z = 0 these differences in the satellite stellar mass functions have been erased. The differences in satellite numbers seen soon after the mergers are driven by several factors, including the timings of significant mergers (with M200c mass ratios >1:30 and bringing in M ≥ 108 M at infall), the masses and satellite populations of the central and merging systems, and the subsequent extended history of smaller mergers. The results persist when measured at fixed central stellar mass rather than fixed time, implying that a host’s recent merger history can be a significant source of scatter when reconstructing its dynamical properties from its satellite population.

Department/s

  • Astrophysics
  • eSSENCE: The e-Science Collaboration

Publishing year

2024-02

Language

English

Pages

2346-2357

Publication/Series

Monthly Notices of the Royal Astronomical Society

Volume

528

Issue

2

Document type

Journal article

Publisher

Oxford University Press

Topic

  • Astronomy, Astrophysics and Cosmology

Keywords

  • galaxies: dwarf
  • galaxies: evolution
  • galaxies: formation
  • galaxies: interactions

Status

Published

ISBN/ISSN/Other

  • ISSN: 0035-8711