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 …

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 …

Context. Measurement of the Galactic neutral atomic hydrogen (H i) column density, NH i,
and brightness temperatures, TB, is of high scientific value for a broad range of astrophysical …

ABSTRACT Context. Measurement of the Galactic neutral atomic hydrogen (H i) column
density, NH i, and brightness temperatures, TB, is of high scientific value for a broad range of …

Abstract The recently initiated Arecibo Legacy Fast ALFA (ALFALFA) survey aims to map∼
7000 deg 2 of the high Galactic latitude sky visible from Arecibo, providing a HI line spectral …

In hierarchical cosmological models, galaxies grow in mass through the continual accretion
of smaller ones. The tidal disruption of these systems is expected to result in loosely bound …

We present global multidimensional numerical simulations of the plasma that pervades the
dark matter haloes of clusters, groups and massive galaxies (the 'intracluster medium'; ICM) …

Hierarchical cold dark matter (CDM) models predict that Milky Way-sized halos contain
several hundred dense low-mass dark matter satellites (the substructure), an order of …

The standard treatment of cooling in cold dark matter haloes assumes that all of the gas
within a 'cooling radius' cools and contracts monolithically to fuel galaxy formation. Here we …

We perform high-resolution N-body+ SPH (smoothed particle hydrodynamics) simulations of
gas-rich dwarf galaxy satellites orbiting within a Milky Way-sized halo and study for the first …