Related papers: HI and Galaxy Formation in Loose Groups
Within the SECCO survey we identified a candidate stellar counterpart to the Ultra Compact High Velocity Cloud (UCHVC) HVC274.68+74.70-123, that was suggested by Adams et al. (2013) as a possible mini-halo within the Local Group of…
High velocity gas that does not conform to Galactic rotation is observed throughout the Galaxy's halo. One component of this gas, HI high velocity clouds (HVCs), have attracted attention since their discovery in the 1960s and remain…
High mass galaxies, with halo masses $M_{200} \ge 10^{10} M_{\odot}$, reveal a remarkable near-linear relation between their globular cluster (GC) system mass and their host galaxy halo mass. Extending this relation to the mass range of…
We investigate the star formation and neutral atomic hydrogen (HI) gas properties of galaxies along three large-scale filaments and two galaxy groups in the wide field around the Virgo cluster. Our goal is to understand how galaxies are…
The existence of stellar halos around galaxies is a natural prediction of the hierarchical nature of the LambdaCDM model. Recent observations of Milky Way-like galaxies have revealed a wide range in stellar halo mass, including cases with…
Green Bank Telescope (GBT) 21cm observations have revealed a faint, yet extensive HI cloud population surrounding the Andromeda Galaxy (M31). The newfound objects are likely analogs to the high-velocity HI clouds (HVCs) seen around the…
We study the formation of the Milky Way's halo in a $\Lambda$CDM cosmology by scaling down a high resolution simulation of the formation of a cluster of galaxies. We determine how much phase-space substructure is left over from the objects…
We consider global HI and optical properties of about three hundred nearby galaxies with V$_0 < 500$ km/s. The majority of them have individual photometric distance estimates. The galaxy sample parameters, e.g. their linear diameters, their…
Current explanation of the overabundance of dark matter subhalos in the Local Group (LG) indicates that there maybe a limit on mass of a halo, which can host a galaxy. This idea can be tested using voids in the distribution of galaxies: at…
In Paper-I we developed a two-phase model to connect dynamically hot galaxies (such as ellipticals and bulges) with the formation of self-gravitating gas clouds (SGCs) associated with the fast assembly of dark matter halos. Here we explore…
In this work, we study the basic statistical properties of HI-selected galaxies extracted from six different semi-analytic models, all run on the same cosmological N-body simulation. One model includes an explicit treatment for the…
Observations of the nearby large galaxies that can be examined in particularly close detail suggest that many have small stellar luminosity fractions in bulges and haloes. Simulations of galaxy formation tend to produce considerably larger…
Galactic halo gas traces inflowing star formation fuel and feedback from a galaxy's disk and is therefore crucial to our understanding of galaxy evolution. In this review, we summarize the multi-wavelength observational properties and…
Ongoing accretion onto galactic disks has been recently theorized to progress via the unstable cooling of the baryonic halo into condensed clouds. These clouds have been identified as analogous to the High-Velocity Clouds (HVCs) observed in…
The formation of galactic discs and the efficiency of star formation within them are issues central to our understanding of galaxy formation. We have developed a detailed and versatile model of disc formation which combines the strengths of…
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 examine the proposal that the HI "high-velocity" clouds (HVCs) surrounding the Milky Way and other disc galaxies form by condensation of the hot galactic corona via thermal instability. Under the assumption that the galactic corona is…
We perform numerical simulations for the formation of the Galactic stellar halo, based on the currently favored cold dark matter (CDM) theory of galaxy formation. Our numerical models, taking into account both dynamical and chemical…
We study the dependence of galaxy clustering on atomic gas mass using a sample of $\sim$16,000 galaxies with redshift in the range of $0.0025<z<0.05$ and HI mass of $M_{\rm HI}>10^8M_{\odot}$, drawn from the 70% complete sample of the…
We use a series of high-resolution N-body simulations of a `Milky-Way' halo, coupled to semi-analytic techniques, to study the formation of our own Galaxy and of its stellar halo. Our model Milky Way galaxy is a relatively young system…