Chemodynamical evolution of the Milky Way disk - I. The solar vicinity

By I. Minchev, C. Chiappini, M. Martig. 2012

319 citations recorded by the source corpus.

[Abridged] In this first paper of this series, we present a new approach for studying the chemo-dynamical evolution in disk galaxies, which consists of fusing disk chemical evolution models with compatible numerical simulations of galactic disks. This method avoids known star formation and chemical enrichment problems encountered in simulations. Here we focus on the Milky Way, by using a detailed thin-disk chemical evolution model and a simulation in the cosmological context, with dynamical properties close to those of our Galaxy. We show that, due to radial migration from mergers at high redshift and the central bar at later times, a sizable fraction of old metal-poor high-[alpha/Fe] stars reaches the solar vicinity. This naturally accounts for a number of recent observations related to both the thin and thick disks, despite the fact that we use thin-disk chemistry only. Although significant radial mixing is present, the slope in the age-metallicity relation is only weakly affected, with a scatter compatible with recent observational work. While we find a smooth density distribution in the [O/Fe]-[Fe/H] plane, we can recover the observed discontinuity by selecting particles according to kinematic criteria used in high-resolution samples to define the thin and thick disks. We outline a new method for estimating the birth place of the Sun and predict that the most likely radius lies in the range 4.4 < r < 7.7 kpc (for a location at r = 8 kpc). A new, unifying model for the Milky Way thick disk is offered, where both mergers and radial migration play a role at different stages of the disk evolution. We show that in the absence of early-on massive mergers the vertical velocity dispersion of the oldest stars is underestimated by a factor of ~2 compared with observations. We can, therefore, argue that the Milky Way thick disk is unlikely to have been formed through a quiescent disk evolution.

Subfields: Astronomy and Astrophysics, Instrumentation

View Paper: https://www.semanticscholar.org/paper/c81e8343214a8a5083697b2b37295d19b5bddad0

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Citations in the corpus

Chemodynamical evolution of the Milky Way disk II: Variations with Galactic radius and height above the disk plane (2014, methodology): “In this work we investigated how chemo-kinematic relations change with position in the Galactic disk, by analyzing the chemo-dynamical model first introduced in Minchev et al. (2013) (paper I).”
Chemodynamics of the Milky Way - I. The first year of APOGEE data (2013, methodology): “The quantification of the effects of radial stellar migration and its causes is thus of crucial importance (see Minchev et al. 2013 for a discussion).”
The age–metallicity structure of the Milky Way disc using APOGEE (2017, background): “Examples of such models include the heating of the old disk by high redshift mergers (e.g. Brook et al. 2004; Villalobos & Helmi 2008; Kazantzidis et al. 2009; Minchev et al. 2013) and the formation of a dual disk by gradual accretion of stars into disk orbits (e.g. Abadi et al. 2003).”
Estimating stellar birth radii and the time evolution of Milky Way’s ISM metallicity gradient (2018, methodology): “Using their hybrid chemo-dynamical model, Minchev et al. (2013) (hereafter, MCM13) showed that SMR stars in their simulated solar neighborhood originated almost exclusively from the radial range 3 < r < 5 kpc (their Fig.”
The vertical metallicity gradients of mono-age stellar populations in the Milky Way with the RAVE and Gaia data (2017, background): “…the existence of a vertical metallicity gradient in a mono-age stellar population of the current Galactic disc stars indicates that a dynamical mechanism, such as radial mixing, built up the vertical metallicity gradient (e.g. Minchev et al. 2013; Kawata et al. 2017; Schönrich & McMillan 2017).”
THE STELLAR POPULATION STRUCTURE OF THE GALACTIC DISK (2015, unknown): “Most other recent simulations, such as those of Minchev et al. (2013), Bird et al. (2013), and Martig et al. (2014) only dissect the disk in terms of mono-age populations and find centrally-peaked radial profiles for all such populations.”
CHEMICAL CARTOGRAPHY WITH APOGEE: LARGE-SCALE MEAN METALLICITY MAPS OF THE MILKY WAY DISK (2013, background): “Minchev et al. (2013) measure vertical gradients at the solar circle for their suite of simulations, in which populations of the same age show no vertical gradient; they find that observed vertical gradients in their simulations are due to mixing of young, metal-rich populations that dominate the…”
Dissecting simulated disc galaxies - I. The structure of mono-age populations (2014, result): “In the sample, the fraction of barred galaxies at z = 0 and higher redshift is realistic when compared to observations (Kraljic et al. 2012), and a detailed chemical modelling of one of the galaxies has shown an interesting match to many features found in the Milky Way (Minchev et al. 2013).”
Numerical simulation of a possible origin of the positive radial metallicity gradient of the thick disk (2013, background): “…satellite accretion (Abadi et al. 2003; Yoachim & Dalcanton 2005), high redshift gas-rich mergers (Brook et al. 2004), radial migration (Roškar et al. 2008; Schönrich & Binney 2009) and a combination of high redshift gas-rich mergers and radial migration (Brook et al. 2012; Minchev et al. 2013).”
Vertical disc heating in Milky Way-sized galaxies in a cosmological context (2015, background): “…of the radially migrated stars in N-body simulations of isolated discs and found that overall radial migration does not have a significant effect on galactic disc thickness, and may even cool the outer parts of the disc in the regime of strong satellite interaction (Minchev et al. 2013, 2014a).”
On the fine structure of the Cepheid metallicity gradient in the Galactic thin disk (2014, background): “On the other hand, chemical evolution models suggest in the same regions iron abundances larger than [Fe/H]∼0.8 (Minchev et al. 2013).”
Constraining the Milky Way assembly history with Galactic Archaeology (2016, methodology): “…be provided by the publisher • Hybrid technique using simulation in a cosmological context + a classical (semi-analytical) chemical evolution model (Minchev et al. 2013, hereafter MCM13): − Avoids problems with SFH and chemical enrichment in fully self-consistent models − Can learn about disc…”
Measuring Radial Orbit Migration in the Galactic Disk (2018, methodology): “This quite precise Rbirth(Sun) estimate is in agreement with the broad prediction from chemo-dynamical simulations of Minchev et al. (2013) (between 4.4 and 7.7 kpc), but differs by 2 kpc from the recent results of Minchev et al. (2018) (7.3±0.6 kpc).”