Related papers: The galaxy "missing dark matter" NGC1052-DF4 is un…
Ordinary baryonic particles (such as protons and neutrons) account for only one-sixth of the total matter in the Universe. The remainder is a mysterious "dark matter" component, which does not interact via electromagnetism and thus neither…
Recent observations suggest that Carina and other nearby dwarf spheroidal galaxies are surrounded by unbound stars tidally stripped by the Milky Way. We run high-resolution N-Body simulations of dwarf galaxies orbiting within the Milky Way…
Tidal dwarf galaxies form during the interaction, collision or merger of massive spiral galaxies. They can resemble "normal" dwarf galaxies in terms of mass, size, and become dwarf satellites orbiting around their massive progenitor. They…
Ultra-compact dwarf galaxies (UCDs) are stellar systems with masses of around 10^7 to 10^8 Msun and half mass radii of 10-100 pc. They have some properties in common with massive globular clusters, however dynamical mass estimates have…
The Milky Way Galaxy contains a large, spherical component which is believed to harbor a substantial amount of unseen matter. Recent observations indirectly suggest that as much as half of this ``dark matter'' may be in the form of old,…
Young tidal dwarf galaxies (TDGs) are observed in the tidal debris of gas-rich interacting galaxies. In contrast to what is generally assumed to be the case for isolated dwarf galaxies, TDGs are not embedded in their own dark matter (DM)…
(Abridged) Any viable cosmological model in which galaxies interact predicts the existence of primordial and tidal dwarf galaxies (TDGs). In particular, in the standard model of cosmology ($\Lambda$CDM), according to the dual dwarf galaxy…
This paper argues that there is a large population of dark galaxies which reveals its presence by the gravitational lensing of quasars, and outnumbers normal galaxies by around 3:1. There are 8 double quasars with a separation greater than…
Using V and I images obtained with WFPC2/HST, we investigate compact stellar structures within tidal tails. Six regions of tidal debris in the four classic ``Toomre Sequence'' mergers: NGC 4038/39 (``Antennae''), NGC 3256, NGC 3921, and NGC…
We use cosmological hydrodynamical simulations of the APOSTLE project along with high-quality rotation curve observations to examine the fraction of baryons in {\Lambda}CDM haloes that collect into galaxies. This 'galaxy formation…
The detection of stars in the process of being tidally removed from globular clusters and dwarf spheroidals in the Galaxy's halo provides a strong constraint on their mass to light ratios and on the extent of their possible dark matter…
Dark matter in galaxies, its abundance, and its distribution remain a subject of long-standing discussion, especially in view of the fact that neither dark matter particles nor dark matter bodies have yet been found. Experts' opinions range…
What galaxy lives in what halo? The answer to this simple question holds important information regarding galaxy formation and evolution. We describe a new statistical technique to link galaxies to their dark matter haloes, or light to mass,…
Over the past decade, a consensus picture has emerged in which roughly a quarter of the universe consists of dark matter. The observational evidence for the existence of dark matter is reviewed: rotation curves of galaxies, weak lensing…
Within the standard cosmological scenario the Universe is found to be filled by obscure components (dark matter and dark energy) for ~95% of its energy budget. In particular, almost all the matter content in the Universe is given by dark…
We report the discovery of a $>1^\circ$ ($\sim50$ kpc) long stellar tidal stream emanating from the dwarf galaxy DDO 44, a likely satellite of Local Volume galaxy NGC 2403 located $\sim70$ kpc in projection from its companion. NGC 2403 is a…
Tidal debris streams from galaxy satellites can provide insight into the dark matter distribution in halos. This is because we have more information about stars in a debris structure than about a purely random population of stars: we know…
Zhao has proposed that the microlensing events observed toward the Large Magellanic Cloud (LMC) could be due to faint stars in a dwarf galaxy or tidal debris lying along the line of sight to the LMC. Zaritsky & Lin claim to have detected…
Recently it was shown that low-mass galaxies containing no dark matter can naturally evolve to dSph-like satellites in a tidal field. Such dSph-like satellites fake total domination by dark matter. If this is correct then it must be…
We examine the observational consequences of the two possible origins for irregular galaxies: formation from collapse of a primordial cloud of gas early in the age of the Universe, and formation from tidal tails in an interaction that could…