Related papers: Accretion by the Galaxy
We use hydrodynamic simulations to examine how the baryonic components of galaxies are assembled, focusing on the relative importance of mergers and smooth accretion in the formation of ~L_* systems. In our primary simulation, which models…
If the favored hierarchical cosmological model is correct, then the Milky Way system should have accreted and subsequently tidally destroyed ~100 low-mass galaxies in the past ~12 Gyr. We model this process using a hybrid semi-analytic plus…
The majority of baryons reside beyond the optical extent of a galaxy in the circumgalactic and intergalactic media (CGM/IGM). Gaseous halos are inextricably linked to the appearance of their host galaxies through a complex story of…
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…
We use cosmological SPH simulations to study the cool, accreted gas in two Milky Way-size galaxies through cosmic time to z=0. We find that gas from mergers and cold flow accretion results in significant amounts of cool gas in galaxy halos.…
The growth-rate and the internal dynamics of galaxy-sized dark-matter haloes depend on their location within the cosmic web. Haloes that sit at the nodes grow in mass till the present time and are dominated by radial orbits. Conversely,…
We use a suite of cosmological hydrodynamic simulations to quantify the accretion rates of baryons into dark matter halos and the resulting baryon mass fractions, as a function of halo mass, redshift, and baryon type (including cold and hot…
We combine the recent determination of the evolution of the cosmic density of molecular gas (H_2) using deep, volumetric surveys, with previous estimates of the cosmic density of stellar mass, star formation rate and atomic gas (HI), to…
The universe's largest galaxies reside at the centers of galaxy clusters and are embedded in hot gas that, if left unchecked, would cool prodigiously and create many more new stars than are actually observed. Cooling can be regulated by…
The cosmic accretion of both dark matter and baryons into halos typically is measured using some evolving virial relation, but recent work suggests that most halo growth at late cosmic time (z < 2) is not physical but is rather the…
Galaxies with Milky Way-like stellar masses have a wide range of bulge and black hole masses; in turn, these correlate with other properties such as star formation history. While many processes may drive bulge formation, major and minor…
Major progress has been made over the last few years in understanding hydrodynamical processes on cosmological scales, in particular how galaxies get their baryons. There is increasing recognition that a large part of the baryons accrete…
We examine the temperature history of gas accreted by forming galaxies in SPH simulations. About half the gas shock heats to roughly the virial temperature of the galaxy potential well before cooling, condensing, and forming stars, but the…
Our Galaxy is a complex machine in which several processes operate simultaneously: metal-poor gas is accreted, is chemically enriched by dying stars, and then drifts inwards, surrendering its angular momentum to stars; new stars are formed…
Evidence for the accretion of cold gas in galaxies has been rapidly accumulating in the past years. HI observations of galaxies and their environment have brought to light new facts and phenomena which are evidence of ongoing or recent…
We examine the accretion and merger histories of central and satellite galaxies in a smoothed particle hydrodynamics (SPH) cosmological simulation that resolves galaxies down to 7e9 M[Sun]. Most friends-of-friends halos in the simulation…
Recent N-body simulations show that the formation of a present-day, galaxy sized dark matter halo in the CDM cosmogony in general consists of an early fast collapse phase, during which the potential associated with a halo is established,…
We develop a new formalism for modeling the formation and evolution of galaxies within a hierarchical universe. Similarly to standard semi-analytical models we trace galaxies inside dark-matter merger-trees. The formalism includes treatment…
We use FIRE simulations to study disk formation in z~0, Milky Way-mass galaxies, and conclude that a key ingredient for the formation of thin stellar disks is the ability for accreting gas to develop an aligned angular momentum distribution…
The hypothesis that massive stars form by accretion can be investigated by simple analytical calculations that describe the effect that the formation of a massive star has on its own accretion flow. Within a simple accretion model that…