Stellar halos may hold some of the best preserved fossils of the formation history of galaxies. They are a natural product of the merging processes that probably take place during the assembly of a galaxy, and hence may well be the most ubiquitous component of galaxies, independently of their ...
We report on a recent ~150-ks long Chandra observation of the ultraluminous infrared galaxy merger NGC 6240, which allows a detailed investigation of the diffuse galactic halo. Extended soft X-ray emission is detected at the 3-sigma confidence level over a diamond-shaped region with projected ...
Once this isunderstood we proceed to measure the shape and orientation of the halo'svelocity ellipsoid and we use this information to put constraints on thegravitational potential of the Galaxy. We use the recently released Gaia DR1catalogue cross-matched to the RAVE dataset for our analysis. ...
We present new limits on the global shape of the dark matter halo in the Andromeda galaxy using and generalizing non-spherical mass models developed by Hayashi & Chiba and compare our results with theoretical predictions of cold dark matter (CDM) models. This is motivated by the fact that CDM...
We conclude that dark matter in spiral galaxies is a problem of geometry, and that Newton's law needs to be corrected to account for the geometry of the mass. Dark matter, the correction to Newton's law in a disk Among the topics are a forming polar ring galaxy in the deep field of...
Does Dark Matter at the Center and in the Halo of the Galaxy Consist of the Same Particles After a discussion of the properties od degenerate fermion balls, we analize the orbits of the star S0-1, which has the smallest projected distance to Sgr A*, in the supermassive black hole as we...
b.A roughly spherical region of relatively dust-free space surrounding a galaxy and extending beyond the visible parts of the galaxy. Galactic halos contain stars (often located in globular clusters), gas, and dark matter. tr.v.ha·loed,ha·lo·ing,ha·loes ...
We show that the outflow velocity levels off at ~10³ km s-1 within the scale of the galaxy disc. Typically, the outflow can reach the virial radius around the time when the AGN shuts off. We show that the outflows are energy-driven, consistent with observations and recent theoretical...
: a circle of light appearing to surround the sun or moon and resulting from refraction or reflection of light by ice particles in the atmosphere 2 : something resembling a halo: such as a : nimbus b : a region of space surrounding a galaxy that is sparsely populated with luminous ...
Using the Hubble Space Telescope, we resolve the red giant branch in the halo of the SO galaxy NGC 3115. We measure magnitudes and (V-I) colours for stars down to 1.5 mag below the tip of the red giant branch. From the brightest stars we estimate a distance modulus (m-M)0=30.21 ±...