English
Related papers

Related papers: Diffusion of radial action in a galactic disc

200 papers

The vertical density distribution of stars in a galactic disc is traditionally obtained by assuming an isothermal vertical velocity dispersion of stars. Recent observations from SDSS, LAMOST, RAVE, Gaia etc show that this dispersion…

Astrophysics of Galaxies · Physics 2020-12-04 Suchira Sarkar , Chanda J. Jog

We present a detailed analysis of the evolution of a simulated isolated disc galaxy. The simulation includes stars, gas, star formation and simple chemical yields. Stellar particles are split in two populations: the old one is present at…

Astrophysics · Physics 2009-11-10 Leo Michel-Dansac , Herve Wozniak

Observations indicate that stars generally lose their protoplanetary discs on a timescale of about 5 Myr. Which mechanisms are responsible for the disc dissipation is still debated. Here we investigate the movement through an ambient medium…

Solar and Stellar Astrophysics · Physics 2017-06-21 T. P. G. Wijnen , O. R. Pols , F. I. Pelupessy , S. Portegies Zwart

From the tangential velocities of stars all over the sky, one can, in a statistical way, infer their 3D velocity distribution. An application to Hipparcos data reveals rich structure in the planar stellar motions: there are several moving…

Astrophysics · Physics 2007-05-23 Walter Dehnen

In earlier papers in this series we determined the intrinsic stellar disc kinematics of fifteen intermediate to late type edge-on spiral galaxies using a dynamical modeling technique. From the photometry we find that intrinsically more…

Astrophysics · Physics 2009-11-10 M. Kregel , P. C. van der Kruit , K. C. Freeman

The stellar metallicity gradients of disc galaxies provide information on the disc assembly, star formation processes and chemical evolution. They also might store information on dynamical processes which could affect the distribution of…

In slowly evolving spherical potentials, $\Phi(r,t)$, radial actions are typically assumed to remain constant. Here, we construct dynamical invariants that allow us to derive the evolution of radial actions in spherical central potentials…

Astrophysics of Galaxies · Physics 2021-09-14 Jan D. Burger , Jorge Peñarrubia , Jesús Zavala

We present evidence that isolated growing discs, subject to internal spiral perturbations, thicken due to both heating \emph{and} radial migration. We show this by demonstrating that the thickness and vertical velocity dispersions of coeval…

Astrophysics of Galaxies · Physics 2015-06-12 Rok Roškar , Victor P. Debattista , Sarah R. Loebman

The emergence of the disc in our Galaxy and the relation of the thick and thin disc formation and evolution is still a matter of debate. The chemo-dynamical characterization of disc stars is key to resolve this question, in particular at…

As heating processes can broaden the distributions of radial actions and the vertical distributions of the Galactic disks, we investigate the vertical distribution of the Galactic disks as a function of radial action based on Apache Point…

Astrophysics of Galaxies · Physics 2023-01-18 Yunpeng Jia , Yuqin Chen , Cuihua Du , Gang zhao

Based on the LAMOST survey and Sloan Digital Sky Survey (SDSS), we use low-resolution spectra of 130,043 F/G-type dwarf stars to study the kinematics and metallicity properties of the Galactic disk. Our study shows that the stars with…

Astrophysics of Galaxies · Physics 2016-10-12 Yingjie Jing , Cuihua Du , Jiayin Gu , Yunpeng Jia , Xiyan Peng , Yuqin Chen , Zhenyu Wu , Jun Ma , Xu Zhou , Zihuang Cao , Yonghui Hou , Yuefei Wang , Yong Zhang

Constraints on the Galactic bulge/bar structure and formation history from stellar kinematics and metallicities mainly come from relatively high-latitude fields (|b|>4) where a complex mix of stellar population is seen. We aim here to…

The effects of the Galactic bar on the velocity distribution of old disc stars in the Solar neighbourhood are investigated using high-resolution 2D test particle simulations. A detailed orbital analysis reveals that the structure of the U-V…

Astrophysics · Physics 2007-05-23 R. Fux

Evidence for wave-like corrugations are well established in the Milky Way and in nearby disc galaxies. These were originally detected as a displacement of the interstellar medium about the midplane, either in terms of vertical distance or…

Astrophysics of Galaxies · Physics 2022-07-28 Thor Tepper-Garcia , Joss Bland-Hawthorn , Ken Freeman

Observations show that radial metallicity gradients in disk galaxies are relatively shallow, if not flat, especially at large galactocentric distances and for galaxies in the high-redshift universe. Given that star formation and metal…

Astrophysics of Galaxies · Physics 2015-06-11 Chao-Chin Yang , Mark Krumholz

We study the evolution of circumstellar disks in 22 young (1 to 100 Myr) nearby (within 500 pc) associations over the entire mass spectrum using photometry covering from the optical to the mid-infrared. We compiled a catalog of 2340…

Solar and Stellar Astrophysics · Physics 2015-06-18 Álvaro Ribas , Bruno Merín , Hervé Bouy , Luke T. Maud

Hydro-dynamical modeling of the inner Galaxy suggest that the radius of the outer Lindblad resonance (OLR) of the Galactic bar lies in the vicinity of the Sun. How does this resonance affect the distribution function in the outer parts of a…

Astrophysics · Physics 2009-05-29 Walter Dehnen

Together optical/near infrared integral field spectroscopy and resolved sub-millimetre interferometry data have mapped the ionised and molecular gas motions in nearly one thousand galaxies at redshifts $z>0.5$. While these measurements have…

Astrophysics of Galaxies · Physics 2025-06-02 E. Wisnioski , J. T. Mendel , R. Leaman , T. Tsukui , H. Übler , N. M. Förster Schreiber

We use 3.6 $\mu$m photometry from the Spitzer Survey of Stellar Structure in Galaxies (S$^{4}$G) to trace the stellar distribution in nearby disk galaxies ($z\approx0$) with total stellar masses $10^{8.5}\lesssim…

Astrophysics of Galaxies · Physics 2016-12-07 Simón Díaz-García , Heikki Salo , Eija Laurikainen

In order to understand the roles of metal flows in galaxy formation and evolution, we analyse our self-consistent cosmological chemo-dynamical simulation of a Milky Way like galaxy during its thin-disc phase. Our simulated galaxy disc…

Astrophysics of Galaxies · Physics 2020-06-03 Fiorenzo Vincenzo , Chiaki Kobayashi