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Related papers: The Thick Disk-Halo Interface

200 papers

We show how the existence of a relation between the star formation rate and the gas density, i.e. the Kennicutt-Schmidt law, implies a continuous accretion of fresh gas from the environment into the discs of spiral galaxies. We present a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Filippo Fraternali , Matteo Tomassetti

The Milky Way stellar disk has both a thin and a thick component. The thin disk is composed mostly of younger stars ($\lesssim$8 Gyr) with a lower abundance of $\alpha$ elements, while the thick disk contains predominantly older stars…

We use high-resolution ($\simeq$ 35pc) hydrodynamical simulations of galaxy formation to investigate the relation between gas accretion and star formation in galaxies hosted by dark matter haloes of mass $10^{12}$ $\mathrm{M_\odot}$ at $z =…

Astrophysics of Galaxies · Physics 2024-09-24 Zuzanna Kocjan , Corentin Cadiou , Oscar Agertz , Andrew Pontzen

We develop a detailed model of the Milky Way (a ``prototypical'' disk galaxy) and extend it to other disks with the help of some simple scaling relations, obtained in the framework of Cold Dark Matter models. This phenomenological…

Astrophysics · Physics 2009-11-07 N. Prantzos

Using reconstructed galaxy star formation histories, we calculate the instantaneous efficiency of galaxy star formation (i.e., the star formation rate divided by the baryon accretion rate) from $z=8$ to the present day. This efficiency…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-27 Peter S. Behroozi , Risa H. Wechsler , Charlie Conroy

As stellar compositions evolve over time in the Milky Way, so will the resulting planet populations. In order to place planet formation in the context of Galactic chemical evolution, we make use of a large ($N = 5\,325$) stellar sample…

Earth and Planetary Astrophysics · Physics 2023-10-11 Jesper Nielsen , Matthew Raymond Gent , Maria Bergemann , Philipp Eitner , Anders Johansen

The satellites of the Milky Way and Andromeda represent the smallest galaxies we can observe in our Universe. In this series of papers we aim to shed light on their formation and evolution using cosmological hydrodynamical simulations. In…

Astrophysics of Galaxies · Physics 2018-01-22 Andrea V. Macciò , Jonas Frings , Tobias Buck , Camilla Penzo , Aaron A. Dutton , Marvin Blank , Aura Obreja

Understanding the Milky Way disc formation requires characterising its structural and kinematic properties as functions of stellar age. Using red giant stars from APOGEE DR17 and Gaia DR3, we model the age-dependent stellar kinematics with…

Astrophysics of Galaxies · Physics 2025-09-30 Natsuki Funakoshi , Daisuke Kawata , Jason L. Sanders , Ioana Ciucă , Robert J. J. Grand , HanYuan Zhāng

Galaxies with Milky Way-like stellar masses have a wide range of bulge and black hole masses; in turn, these correlate with other properties such as star formation history. While many processes may drive bulge formation, major and minor…

[Abridged] We map the stellar age distribution ($\lesssim 1$ Gyr) across a 6kpc$\,\times\,$6kpc area of the Galactic disc to constrain our Galaxy's recent star-formation history. Our modelling draws on the sample of Zari et al. (2021) that…

Astrophysics of Galaxies · Physics 2022-12-21 E. Zari , N. Frankel , H. -W. Rix

In this paper we present a new chemical evolution model for the Galaxy which assumes two main infall episodes for the formation of halo-thick disk and thin disk, respectively. We do not try to take into account explicitly the evolution of…

Astrophysics · Physics 2009-10-28 C. Chiappini , F. Matteucci , R. Gratton

High spatial and spectral resolution observations of star formation and kinematics in early galaxies have shown that two-thirds are massive rotating disk galaxies with the remainder being less massive non-rotating objects. The line of sight…

A simple chemical enrichment code is described where the two basic mechanisms driving the evolution of the ages and metallicities of the stellar populations are the star formation efficiency and the fraction of gas ejected from the galaxy.…

Astrophysics · Physics 2009-11-06 I. Ferreras , J. Silk

One of the last missing pieces in the puzzle of galaxy formation and evolution through cosmic history is a detailed picture of the role of the cold gas supply in the star-formation process. Cold gas is the fuel for star formation, and thus…

We present first results from a spectroscopic survey of 2000 F/G stars 0.5--5kpc from the Galactic plane, obtained with the 2dF facility on the AAT. These data show the mean rotation velocity of the thick disk about the Galactic center a…

Astrophysics · Physics 2009-11-07 Gerard Gilmore , Rosemary F. G. Wyse , John E. Norris

The cosmic star formation rate density first increases with time towards a pronounced peak 10 Gyrs ago (or z=1-2) and then slows down, dropping by more than a factor 10 since z=1. The processes at the origin of the star formation quenching…

Astrophysics of Galaxies · Physics 2017-01-11 F. Combes , the PHIBSS collaboration

The formation and evolution of galactic disks are complex phenomena, where gas and star dynamics are coupled through star formation and the related feedback. The physical processes are so numerous and intricate that numerical models focus,…

Astrophysics · Physics 2009-11-07 B. Semelin , F. Combes

A period of quenching between the formation of the thick and thin disks of the Milky Way has been recently proposed to explain the observed age-[{\alpha}/Fe] distribution of stars in the solar neighbourhood. However, robust constraints on…

Studies of elemental abundances in stars belonging to the thin and the thick disk of our Galaxy are reviewed. Edvardsson et al. (1993) found strong evidence of [alpha/Fe] variations among F and G main sequence stars with the same [Fe/H] and…

Astrophysics · Physics 2007-05-23 Poul E. Nissen

We review observational evidence bearing on the formation of a prototypical large spiral galaxy, the Milky Way. New ground- and space-based studies of globular star clusters and dwarf spheroidal galaxies provide a wealth of information to…