Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

Effects of secular growth and mergers on the evolution of metallicity gradients and azimuthal variations in a Milky Way-like galaxy

Renaud, Florent LU ; Ratcliffe, Bridget ; Minchev, Ivan ; Haywood, Misha ; Di Matteo, Paola ; Agertz, Oscar LU and Romeo, Alessandro B. (2025) In Astronomy and Astrophysics 694.
Abstract

We analyzed the evolution of the radial profiles and the azimuthal variations of the stellar metallicities from the VINTERGATAN simulation of a Milky Way-like galaxy. We find that negative gradients exist as soon as the disk settles at high redshift, and are maintained throughout the long-term evolution of the galaxy, including during major merger events. The inside-out growth of the disk and an overall outward radial migration tend to flatten these gradients in time. Major merger events only have a moderate and shortlived imprint on the [Fe/H] distributions with almost no radial dependence. The reason lies in the timescale for enrichment in Fe being significantly longer than the duration of the starbursts episodes, themselves slower... (More)

We analyzed the evolution of the radial profiles and the azimuthal variations of the stellar metallicities from the VINTERGATAN simulation of a Milky Way-like galaxy. We find that negative gradients exist as soon as the disk settles at high redshift, and are maintained throughout the long-term evolution of the galaxy, including during major merger events. The inside-out growth of the disk and an overall outward radial migration tend to flatten these gradients in time. Major merger events only have a moderate and shortlived imprint on the [Fe/H] distributions with almost no radial dependence. The reason lies in the timescale for enrichment in Fe being significantly longer than the duration of the starbursts episodes, themselves slower than dynamical mixing during typical interactions. It results in signatures of major mergers becoming undetectable in [Fe/H] only a few megayears after pericenter passages. We note that considering other tracers like the warm interstellar medium, or monitoring the evolution of the metallicity gradient as a single value instead of a radial full profile could lead to different interpretations; we warn against oversimplifying this complex problem.

(Less)
Please use this url to cite or link to this publication:
author
; ; ; ; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Galaxy: disk, Galaxy: evolution, Methods: numerical
in
Astronomy and Astrophysics
volume
694
article number
A56
publisher
EDP Sciences
external identifiers
  • scopus:85217012720
ISSN
0004-6361
DOI
10.1051/0004-6361/202452219
language
English
LU publication?
yes
id
b7454284-576f-4f0a-bbb7-d411940db667
date added to LUP
2025-04-07 14:52:57
date last changed
2025-04-07 14:53:47
@article{b7454284-576f-4f0a-bbb7-d411940db667,
  abstract     = {{<p>We analyzed the evolution of the radial profiles and the azimuthal variations of the stellar metallicities from the VINTERGATAN simulation of a Milky Way-like galaxy. We find that negative gradients exist as soon as the disk settles at high redshift, and are maintained throughout the long-term evolution of the galaxy, including during major merger events. The inside-out growth of the disk and an overall outward radial migration tend to flatten these gradients in time. Major merger events only have a moderate and shortlived imprint on the [Fe/H] distributions with almost no radial dependence. The reason lies in the timescale for enrichment in Fe being significantly longer than the duration of the starbursts episodes, themselves slower than dynamical mixing during typical interactions. It results in signatures of major mergers becoming undetectable in [Fe/H] only a few megayears after pericenter passages. We note that considering other tracers like the warm interstellar medium, or monitoring the evolution of the metallicity gradient as a single value instead of a radial full profile could lead to different interpretations; we warn against oversimplifying this complex problem.</p>}},
  author       = {{Renaud, Florent and Ratcliffe, Bridget and Minchev, Ivan and Haywood, Misha and Di Matteo, Paola and Agertz, Oscar and Romeo, Alessandro B.}},
  issn         = {{0004-6361}},
  keywords     = {{Galaxy: disk; Galaxy: evolution; Methods: numerical}},
  language     = {{eng}},
  publisher    = {{EDP Sciences}},
  series       = {{Astronomy and Astrophysics}},
  title        = {{Effects of secular growth and mergers on the evolution of metallicity gradients and azimuthal variations in a Milky Way-like galaxy}},
  url          = {{http://dx.doi.org/10.1051/0004-6361/202452219}},
  doi          = {{10.1051/0004-6361/202452219}},
  volume       = {{694}},
  year         = {{2025}},
}