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相关论文: Revisiting the Stellar Velocity Ellipsoid - Hubble…

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The velocity dispersion of galaxies on small scales ($r\sim1h^{-1}$ Mpc), $\sigma_{12}(r)$, can be estimated from the anisotropy of the galaxy-galaxy correlation function in redshift space. We apply this technique to ``mock-catalogs''…

天体物理学 · 物理学 2009-10-28 Rachel S. Somerville , Joel R. Primack , Richard Nolthenius

We simulate the formation and chemodynamical evolution of 128 elliptical galaxies using a GRAPE-SPH code that includes various physical processes that are associated with the formation of stellar systems: radiative cooling, star formation,…

天体物理学 · 物理学 2009-11-11 Chiaki Kobayashi

Progress in the theory of stellar convection over the past decade is reviewed. The similarities and differences between convection in stellar envelopes and laboratory convection at high Rayleigh numbers are discussed. Direct numerical…

天体物理学 · 物理学 2007-05-23 H. C. Spruit

We derive the disk masses of 18 spiral galaxies of different luminosity and Hubble Type, both by mass modelling their rotation curves and by fitting their SED with spectro-photometric models. The good agreement of the estimates obtained…

天体物理学 · 物理学 2009-11-13 Paolo Salucci , Irina A. Yegorova , Niv Drory

This paper presents some new statistical correlations between the properties of disks and spiral arms with some physical properties of galaxies. Our results show that the thickness of spiral disks tend to diminish along the Hubble sequence…

天体物理学 · 物理学 2009-11-07 Jun Ma

We study the relationship between the stability level of late-type galaxy disks and their star-formation activity using integral-field gaseous and stellar kinematic data. Specifically, we compare the two-component (gas+stars) stability…

The radial density profiles of stellar galaxy discs can be well approximated as an exponential. Compared to this canonical form, however, the profiles in the majority of disc galaxies show downward or upward breaks at large radii.…

We study the eccentricity distribution of a thick disc sample of stars observed in the Radial Velocity Experiment (RAVE) and compare it to that expected in four simulations of thick disc formation in the literature (accretion of satellites,…

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…

天体物理学 · 物理学 2009-11-10 M. Kregel , P. C. van der Kruit , K. C. Freeman

We have performed TreeSPH simulations of galaxy formation in a standard LCDM cosmology, including effects of star formation, energetic stellar feedback processes and a meta-galactic UV field, and obtain a mix of disk, lenticular and…

天体物理学 · 物理学 2009-11-07 Jesper Sommer-Larsen , Martin Gotz , Laura Portinari

The mass-to-light ratio (M/L) is a key parameter in decomposing galactic rotation curves into contributions from the baryonic components and the dark halo of a galaxy. One direct observational method to determine the disc M/L is by…

星系天体物理 · 物理学 2020-10-13 S. Aniyan , A. A. Ponomareva , K. C. Freeman , M. Arnaboldi , O. E. Gerhard , L. Coccato , K. Kuijken , M. Merrifield

We examined radial variations in molecular-gas based star formation efficiency (SFE), which is defined as star formation rate per unit molecular gas mass, for 80 galaxies selected from the CO Multi-line Imaging of Nearby Galaxies project…

Stellar feedback plays a crucial role in regulating baryon cycles of a galactic ecosystem, and may manifest itself in the formation of superbubbles in the interstellar medium. In this work, we used a set of high-resolution simulations to…

星系天体物理 · 物理学 2024-03-20 Chengzhe Li , Hui Li , Wei Cui , Federico Marinacci , Laura V. Sales , Mark Vogelsberger , Paul Torrey

We study the neutral hydrogen properties of a sample of 20 bulgeless disk galaxies (Sd - Sdm Hubble types), an interesting class that can be used to constrain galaxy formation and evolution, especially the role of mergers versus internal…

宇宙学与河外天体物理 · 物理学 2015-05-20 Linda C. Watson , Eva Schinnerer , Paul Martini , Torsten Boeker , Ute Lisenfeld

The kinematics of galaxies with 10 megaparsecs (10 Mpc) of the Milky Way is investigated using published distances and radial velocities. With respect to the average Hubble flow (isotropic or simple anisotropic), there is NO systematic…

天体物理学 · 物理学 2009-11-07 Alan B. Whiting

Spiral galaxies are observed to exhibit a range of morphologies, in particular in the shape of spiral arms. A key diagnostic parameter is the pitch angle, which describes how tightly wound the spiral arms are. Observationally and…

星系天体物理 · 物理学 2015-06-11 Robert J. J. Grand , Daisuke Kawata , Mark Cropper

We show that the observed Velocity Dispersion Function of E/S0 galaxies matches strikingly well the distribution function of virial velocities of massive halos virializing at z > 1.5, as predicted by the standard hierarchical clustering…

天体物理学 · 物理学 2009-11-11 M. Cirasuolo , F. Shankar , G. L. Granato , G. De Zotti , L. Danese

The stellar velocity dispersion ($\sigma$) of massive elliptical galaxies is a key ingredient in breaking the mass-sheet degeneracy and obtaining precise and accurate cosmography from gravitational time delays. The relative uncertainty on…

I use N-body simulations with two mass species of particles to demonstrate that disk galaxy simulations are subject to collisional relaxation at a higher rate than is widely assumed. Relaxation affects the vertical thickness of the disk…

宇宙学与河外天体物理 · 物理学 2015-06-15 J. A. Sellwood

Elliptical galaxies comprise primarily old stars, which collectively generate a long-lasting feedback via stellar mass-loss and Type Ia SNe. This feedback can be traced by X-ray-emitting hot gas in and around such galaxies, in which little…

星系天体物理 · 物理学 2015-05-18 Q. Daniel Wang