Exploring the Origin of Thick Disks Using the NewHorizon and Galactica Simulations

@article{Park2021ExploringTO,
  title={Exploring the Origin of Thick Disks Using the NewHorizon and Galactica Simulations},
  author={Minjung Park and Sukyoung K. Yi and S{\'e}bastien Peirani and Christophe Pichon and Yohan Dubois and Hoseung Choi and Julien Devriendt and Sugata Kaviraj and Taysun Kimm and Katarina Kraljic and Marta Volonteri},
  journal={The Astrophysical Journal Supplement Series},
  year={2021},
  volume={254}
}
Ever since a thick disk was proposed to explain the vertical distribution of the Milky Way disk stars, its origin has been a recurrent question. We aim to answer this question by inspecting 19 disk galaxies with stellar mass greater than 1010 M ⊙ in recent cosmological high-resolution zoom-in simulations: galactica and NewHorizon. The thin and thick disks are reasonably reproduced by the simulations with scale heights and luminosity ratios as observed. We then spatially classify the thin and… 

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References

SHOWING 1-10 OF 102 REFERENCES

The dual origin of the Galactic thick disc and halo from the gas-rich Gaia–Enceladus Sausage merger

We analyse a set of cosmological magneto-hydrodynamic simulations of the formation of Milky Way-mass galaxies identified to have a prominent radially anisotropic stellar halo component similar to the

Co-formation of the thin and thick discs revealed by APOGEE-DR16 andGaia-DR2

Since thin disc stars are younger than thick disc stars on average, the thin disc is predicted by some models to start forming after the thick disc had formed, around 10 Gyr ago. Accordingly, no

VINTERGATAN – II. The history of the Milky Way told by its mergers

Using the VINTERGATAN cosmological zoom simulation, we explore the contributions of the in situ and accreted material, and the effect of galaxy interactions and mergers in the assembly of a Milky

VINTERGATAN – I. The origins of chemically, kinematically, and structurally distinct discs in a simulated Milky Way-mass galaxy

Spectroscopic surveys of the Milky Way’s stars have revealed spatial, chemical, and kinematical structures that encode its history. In this work, we study their origins using a cosmological zoom

Chemical enrichment and radial migration in the Galactic disc – the origin of the [αFe] double sequence

The ([α/Fe], [Fe/H]) distribution of Milky Way stars shows at least two distinct sequences, which have traditionally been associated with the thin and thick disc components. The abundance

Introducing the NEWHORIZON simulation: Galaxy properties with resolved internal dynamics across cosmic time

Hydrodynamical cosmological simulations are increasing their level of realism by considering more physical processes and having greater resolution or larger statistics. However, usually either the

The recurrent impact of the Sagittarius dwarf on the Milky Way star formation history

Satellites orbiting disc galaxies can induce phase space features such as spirality, vertical heating and phase-mixing in their discs. Such features have also been observed in our own Galaxy, but the

Simulations of Galaxy Formation in a Λ Cold Dark Matter Universe. II. The Fine Structure of Simulated Galactic Disks

We present a detailed analysis of the disk component of a simulated galaxy formed in the ΛCDM cosmogony. At redshift z = 0, two distinct dynamical components are easily identified solely on the basis

The structure and dynamical evolution of the stellar disc of a simulated Milky Way-mass galaxy

We study the structure, age and metallicity gradients, and dynamical evolution using a cosmological zoom-in simulation of a Milky Way-mass galaxy from the Feedback in Realistic Environments project.

Structural Parameters of Thin and Thick Disks in Edge-on Disk Galaxies

We analyze the global structure of 34 late-type, edge-on, undisturbed, disk galaxies spanning a wide range of mass. We measure structural parameters for the galaxies using two-dimensional
...