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相关论文: Mergers and Disk Survival in LCDM

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We study the merger histories of galaxy dark matter halos using a high resolution LCDM N-body simulation. Our merger trees follow ~17,000 halos with masses M_0 = (10^11--10^13) Msun at z=0 and track accretion events involving objects as…

天体物理学 · 物理学 2010-11-05 Kyle R. Stewart , James S. Bullock , Risa H. Wechsler , Ariyeh H. Maller , Andrew R. Zentner

We use N-body simulations and observationally-normalized relations between dark matter halo mass, stellar mass, and cold gas mass to derive robust, arguably inevitable expectations about the baryonic content of major mergers out to redshift…

宇宙学与河外天体物理 · 物理学 2009-11-14 Kyle R. Stewart , James S. Bullock , Risa H. Wechsler , Ariyeh H. Maller

Most Galaxy-sized systems (M_host ~ 10^12 M_sun) in the LCDM cosmology are expected to have accreted at least one satellite with a total mass M_sat ~ 10^11 M_sun = 3M_disk in the past 8 Gyr. Analytic and numerical investigations suggest…

天体物理学 · 物理学 2009-03-10 Chris W. Purcell , Stelios Kazantzidis , James S. Bullock

About two-thirds of present-day, large galaxies are spirals such as the Milky Way or Andromeda, but the way their thin rotating disks formed remains uncertain. Observations have revealed that half of their progenitors, six billion years…

宇宙学与河外天体物理 · 物理学 2015-06-05 M. Puech , F. Hammer , P. F. Hopkins , E. Athanassoula , H. Flores , M. Rodrigues , J. L. Wang , Y. B. Yang

We employ a high-resolution LCDM N-body simulation to present merger rate predictions for dark matter halos and investigate how common merger-related observables for galaxies--such as close pair counts, starburst counts, and the…

天体物理学 · 物理学 2009-11-14 Kyle R. Stewart , James S. Bullock , Elizabeth J. Barton , Risa H. Wechsler

Previous models of galactic disk heating in interactions invoke restrictive assumptions not necessarily valid in modern LCDM contexts: that satellites and orbits are rigid and circular, with slow decay over many orbital times from dynamical…

天体物理学 · 物理学 2009-11-13 Philip F. Hopkins , Lars Hernquist , Thomas J. Cox , Joshua D. Younger , Gurtina Besla

We use a semi-analytic model of halo formation to study the dynamical history of giant field galaxies like the Milky Way. We find that in a concordance LCDM cosmology, most isolated disk galaxies have remained undisturbed for 8-10 Gyr, such…

天体物理学 · 物理学 2009-11-07 James E. Taylor , Arif Babul

In a LCDM cosmology, the Milky Way accretes satellites into the stellar disc. We use cosmological simulations to assess the frequency of near disc plane and higher inclination accretion events, and collisionless simulations of satellite…

天体物理学 · 物理学 2009-11-13 J. I. Read , G. Lake , O. Agertz , Victor P. Debattista

(Abridged) The violent hierarchical nature of the LCDM cosmology poses serious difficulties for the formation of disk galaxies. To help resolve these issues, we describe a new, merger-driven scenario for the cosmological formation of disk…

We study the formation of disk-dominated galaxies in a LCDM universe. Their existence is considered to be a challenge for the LCDM cosmology, because galaxy mergers isotropize stellar disks and trigger angular momentum transport in gas…

宇宙学与河外天体物理 · 物理学 2009-11-13 Jun Koda , Milos Milosavljevic , Paul R. Shapiro

(Abridged) We conduct a series of high-resolution, dissipationless N-body simulations to investigate the cumulative effect of substructure mergers onto thin disk galaxies in the context of the LCDM paradigm of structure formation. Our…

Using the deepest and the most complete set of observations of distant galaxies, we investigate how extended disks could have formed. Observations include spatially-resolved kinematics, detailed morphologies and photometry from UV to…

宇宙学与河外天体物理 · 物理学 2015-05-30 F. Hammer , M. Puech , H. Flores , E. Athanassoula , Y. B. Yang , J. L. Wang , M. Rodrigues , S. Fouquet

We analyze the merger and assembly histories of Milky Way (MW) and Andromeda (M31)-like galaxies to quantify how, and how often, disk galaxies of this mass can survive recent major mergers (stellar mass ratio $\ge$ 1:4). For this, we use…

[Abridged] Typical disc galaxies forming in a LambdaCDM cosmology encounter a violent environment, where they often experience mergers with massive satellites. The fact that disc galaxies are ubiquitous in the local Universe suggests that a…

星系天体物理 · 物理学 2017-11-15 Andreea S. Font , Ian G. McCarthy , Amandine M. C. Le Brun , Robert A. Crain , Lee S. Kelvin

The majority of massive star-forming galaxies at $z\sim2$ have velocity gradients suggestive of rotation, in addition to large amounts of disordered motions. In this paper, we demonstrate that it is challenging to distinguish the regular…

New simulations are presented which investigate the formation of smaller groups of galaxies in a CDM like universe. The simulations follow the evolution of dark matter and gas and are performed with an SPH code adapted for the…

天体物理学 · 物理学 2016-08-30 Matthias Steinmetz

We study the growth of dark matter halos in the concordance LCDM cosmology using several N-body simulations of large cosmological volumes. We build merger trees from the Millennium and Millennium-II simulations, covering a range 10^9-10^15…

宇宙学与河外天体物理 · 物理学 2010-07-21 Shy Genel , Nicolas Bouché , Thorsten Naab , Amiel Sternberg , Reinhard Genzel

The cold dark matter halo mass function is much steeper than the galaxy stellar mass function on galactic and subgalactic scales. This difference is usually reconciled by assuming that the galaxy formation efficiency drops sharply with…

宇宙学与河外天体物理 · 物理学 2015-06-03 Ismael Ferrero , Mario G. Abadi , Julio F. Navarro , Laura V. Sales , Sebastian Gurovich

Minor accretion events with mass ratio M_sat : M_host ~ 1:10 are common in the context of LCDM cosmology. We use high-resolution simulations of Galaxy-analogue systems to show that these mergers can dynamically eject disk stars into a…

星系天体物理 · 物理学 2015-05-14 Chris W. Purcell , James S. Bullock , Stelios Kazantzidis

We use numerical simulations to examine the structure of merger remnants resulting from collisions of gas-rich spiral galaxies. When the gas fraction of the progenitors is small, the remnants structurally and kinematically resemble…

天体物理学 · 物理学 2009-11-10 Volker Springel , Lars Hernquist
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