English
Related papers

Related papers: The Galactic Thick Disk: An Observational Perspect…

200 papers

The disc structure of the Milky Way is marked by a chemical dichotomy, with high-alpha and low-alpha abundance sequences, traditionally identified with the geometric thick and thin discs. This identification is aided by the old ages of the…

Present-day disc galaxies often exhibit distinct thin and thick discs. The formation mechanisms of the two discs and the timing of their onset remain open questions. To address these questions, we select edge-on galaxies from flagship JWST…

Astrophysics of Galaxies · Physics 2025-04-11 Takafumi Tsukui , Emily Wisnioski , Joss Bland-Hawthorn , Ken Freeman

Recent large scale surveys of galactic bulge stars allowed to build a detailed map of the bulge kinematics. The bulge exhibits cylindrical rotation consistent with a disky origin which evolved through bar driven secular evolution. However…

Astrophysics of Galaxies · Physics 2016-07-06 Carine Babusiaux

Most of the visible mass in a typical spiral galaxy is distributed in a thin disk, with a radial extent much larger than its thickness. While the planar disk structure, including non-axisymmetric features such as spiral structure, has been…

Astrophysics of Galaxies · Physics 2025-07-04 Chanda J. Jog

The determination of chemical abundances in star-forming galaxies and the study of their evolution on cosmological timescales are powerful tools for understanding galaxy formation and evolution. This contribution presents the latest results…

Astrophysics · Physics 2007-05-23 T. Contini , M. -A. Treyer , M. Mouhcine , M. Sullivan , R. S. Ellis

Since stellar populations enhance particular element abundances according to the yields and lifetimes of the stellar progenitors, the chemical evolution of galaxies serves as one of the key tools that allows the tracing of galaxy evolution.…

Astrophysics · Physics 2007-05-23 G. Hensler , A. Rieschick

The disks that orbit young stars are the essential conduits and reservoirs of material for star and planet formation. Their structures, meaning the spatial variations of the disk physical conditions, reflect the underlying mechanisms that…

Earth and Planetary Astrophysics · Physics 2020-11-11 Sean M. Andrews

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 least-squares fitting to our $R$-band photometry.…

Astrophysics · Physics 2008-11-26 Peter Yoachim , Julianne J. Dalcanton

Observations reveal that mature spiral galaxies consist of stars, gases and plasma approximately distributed in a thin disk of circular shape, usually with a central bulge. The rotation velocities quickly increase from the galactic center…

Astrophysics · Physics 2008-04-22 C. F. Gallo , James Q. Feng

The Milky Way is a barred galaxy whose central bulge has a box/peanut shape and consists of multiple stellar populations with different orbit distributions. This review describes dynamical and chemo-dynamical equilibrium models for the…

Astrophysics of Galaxies · Physics 2018-08-22 Ortwin Gerhard

I review recent observational progress concerning the evolution of the morphological distribution of galaxies in the rich cluster environment and in the faint field population. By coupling HST imagery with ground-based spectroscopic…

Astrophysics · Physics 2007-05-23 Richard S Ellis

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

Galactic discs are known to have a complex multilayer structure. An in-depth study of the stellar population properties of the thin and thick components can elucidate the formation and evolution of disc galaxies. Even though thick discs are…

Astrophysics of Galaxies · Physics 2020-04-01 Anastasia V. Kasparova , Ivan Yu. Katkov , Igor V. Chilingarian

In this review I concentrate on three areas related to structure of disks in spiral galaxies. First I will review the work on structure, kinematics and dynamics of stellar disks. Next I will review the progress in the area of flaring of HI…

Astrophysics of Galaxies · Physics 2015-05-18 P. C. van der Kruit

Galaxy masses play a fundamental role in our understanding of structure formation models. This review addresses the variety and reliability of mass estimators that pertain to stars, gas, and dark matter. The different sections on masses…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-29 S. Courteau , M. Cappellari , R. S. de Jong , A. A. Dutton , E. Emsellem , H. Hoekstra , L. V. E. Koopmans , G. A. Mamon , Claudia Maraston , T. Treu , L. M. Widrow

We study the orbital properties of stars in four (published) simulations of thick disks formed by: i) accretion from disrupted satellites, ii) heating of a pre-existing thin disk by a minor merger, iii) radial migration and iv) gas rich…

In this contribution we summarize recent achievements by our group on the understanding of the structure of the outer Galactic disk, with particular emphasis to the outer disk extent, and the spiral structure beyond the solar circle.

Astrophysics of Galaxies · Physics 2013-10-08 G. Carraro , G. Perren , R. A. Vázquez , A. Moitinho

In this review I outline some ideas in chemical evolution, necessary for understanding the evolution of galaxies from measured elemental abundance ratios. I then discuss abundance results from studies of Local Group dwarf galaxies and the…

Astrophysics of Galaxies · Physics 2010-11-24 Andrew McWilliam

We investigate thin and thick stellar disc formation in Milky-Way-mass galaxies using twelve FIRE-2 cosmological zoom-in simulations. All simulated galaxies experience an early period of bursty star formation that transitions to a late-time…

Some factors connecting the evolutionary histories of galaxies with the characteristics of their cluster systems are reviewed. Unanswered questions include: How is one to understand the observation that some globular cluster systems have…

Astrophysics · Physics 2007-05-23 Sidney van den Bergh