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相关论文: Dissecting simulated disc galaxies II: the age-vel…

200 篇论文

We present stellar age profiles for 64 Virgo cluster disk galaxies whose analysis poses a challenge for current galaxy formation models. Our results can be summarized as follows: first, and contrary to observations of field galaxies, these…

宇宙学与河外天体物理 · 物理学 2015-06-04 Joel C. Roediger , Stephane Courteau , Patricia Sanchez-Blazquez , Michael McDonald

We investigate the age-chemical abundance structure of the outer Galactic disc at a galactocentric distance of r > 10 kpc as recently revealed by the SDSS/APOGEE survey. Two sequences are present in the [alpha/Fe]-[Fe/H] plane with…

We investigate the rotational evolution of young stars through Monte Carlo simulations. We simulate 280,000 stars, each of which is assigned a mass, a rotational period, and a mass accretion rate. The mass accretion rate depends on mass and…

太阳与恒星天体物理 · 物理学 2015-06-11 M. J. Vasconcelos , J. Bouvier

A spectral evolution model of galaxies that includes both stellar and dust effects is newly built. xApplying the model to 22 nearby starburst galaxies, we have shown that far infrared luminosity of galaxies helps to break the age-dustiness…

天体物理学 · 物理学 2009-10-31 Toshinobu Takagi , Nobuo Arimoto , Vladas Vansevicius

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…

星系天体物理 · 物理学 2025-06-02 E. Wisnioski , J. T. Mendel , R. Leaman , T. Tsukui , H. Übler , N. M. Förster Schreiber

I present the results of Monte-Carlo orbital simulations of Galactic Neutron Stars (NSs). The simulations take into account the up-to-date observed NS space and velocity distributions at birth, and account for their formation rate. I…

星系天体物理 · 物理学 2010-11-02 E. O. Ofek

The Milky Way was shaped by the mergers with several galaxies in the past. We search for remnant stars that were born in these foreign galaxies and assess their ages in an effort to put upper limits on the merger times and thereby better…

Several massive ($M_{*} > 10^8 M_{\odot}$), high-redshift ($z = 8-10$) galaxies have recently been discovered to contain stars with ages of several hundred million years, pushing the onset of star formation in these galaxies back to…

星系天体物理 · 物理学 2021-06-02 Clarke J. Esmerian , Nickolay Y. Gnedin

In this Letter, we analyse the distributions of stellar ages in Giant Molecular Clouds (GMCs) in spiral arms, inter-arm spurs, and at large galactic radii, where the spiral arms are relatively weak. We use the results of numerical…

星系天体物理 · 物理学 2015-06-17 C. L. Dobbs , J. E. Pringle , T. Naylor

We study the stellar properties of 44 face-on spiral galaxies from the Calar Alto Legacy Integral Field Area survey via full spectrum fitting techniques. We compare the age profiles with the surface brightness distribution in order to…

We present recent progress on quantitative estimation of stellar ages using ind icators such as theoretical evolutionary tracks, rotation, rotation-driven chrom ospheric and coronal activity, and lithium depletion. Our focus is on roughly…

天体物理学 · 物理学 2009-11-13 Lynne Hillenbrand , Eric Mamajek , John Stauffer , David Soderblom , John Carpenter , Michael Meyer

We propose that the lower bound of the stellar radial velocity dispersion c_r of an equilibrium stellar disk is determined by the gravitational stability condition. We compared the estimates of stellar velocity dispersion at radii r>(1.5 -…

天体物理学 · 物理学 2007-05-23 A. V. Zasov , A. V. Khoperskov , N. V. Tyurina

We revisit the stellar velocity distribution in the Galactic bulge/bar region with APOGEE DR16 and {\it Gaia} DR2, focusing in particular on the possible high-velocity (HV) peaks and their physical origin. We fit the velocity distributions…

The RAVE survey, combined with proper motions and distance estimates, can be used to study in detail stellar kinematics in the extended solar neighbourhood (solar suburb). Using the red clump, we examine the mean velocity components in 3D…

We present a fully consistent evolutionary disc model of the solar cylinder. The model is based on a sequence of stellar sub-populations described by the star formation history (SFR) and the dynamical heating law (given by the age-velocity…

星系天体物理 · 物理学 2010-11-23 A. Just , H. Jahreiss

The origin of thick disks and their evolutionary connection with thin disks are still a matter of debate. We provide new insights into this topic by connecting the stellar populations of thick disks at redshift $z=0$ with their past…

The kinematics of the $\epsilon$ Cha young stellar association close to the Sun has been studied based on a list of candidate stars from the Dickson-Vandervelde work. The working sample consists of 26 stars with parallaxes, proper motions…

星系天体物理 · 物理学 2024-06-04 Vadim V. Bobylev , Anisa T. Bajkova

We have done a detailed study on the structural and kinematical properties of lenticular and early- and late-type spiral galaxies with bars, aiming to explore the formation and evolution processes of stellar bars in galaxies, and their…

天体物理学 · 物理学 2009-11-10 Dimitri Alexei Gadotti

Pulsar motions in our Galaxy from their birth until 2 Gyr are studied statistically via Monte-Carlo simulation of $2\times 10^5$ pulsars with the best available representation of the Galactic potential. We find that the distribution of…

天体物理学 · 物理学 2009-11-10 X. H. Sun , J. L. Han

In the local Universe, the existence of very young galaxies (VYGs), having formed at least half their stellar mass in the last 1 Gyr, is debated. We predict the present-day fraction of VYGs among central galaxies as a function of galaxy…