We present an observational survey program using planetary nebulae, globular clusters, and X-ray emission to probe the halos of early-type galaxies. We review evidence for scanty dark matter halos around ordinary elliptical galaxies, and discuss the possible implications. We also present measurements of rotation in the halos.

AIMS To calculate the diameter of halos perceived by patients with multifocal intraocular lenses (IOLs) and to stimulate halos in patients with refractive multifocal IOLs in a clinical experiment. METHODS Calculations were done to show the diameter of halos in the case of the bifocal intraocular lens. 24 patients with a refractive multifocal IOLs and five patients with a monofocal IOL were as...

We study the diversity of the density profiles of dark matter halos based on a large set of high-resolution cosmological simulations of 256 particles. The cosmological models include four scale-free models and three representative cold dark matter models. The simulations have good force resolution. In each cosmological model, there are about 400 massive halos which have more than 10 particles w...

The promising neutralino dark matter particles generically condense into numerous earth-mass dark halos with smaller substructures suppressed by free streaming[1]. The recent Letter to Nature[2] claims that these 0.01pc-sized dense halos emerged at redshifts 60–26 are rarely destructed inside galaxies, hence the nearest halos at about 0.1pc from Earth are bright in annihilation-powered gamma-ra...

We predict the fraction of dark halo lenses, that is, the fraction of lens systems produced by the gravitational potential of dark halos, on the basis of a simple parametric model of baryonic compression. The fraction of dark halo lenses primarily contains information on the effect of baryonic compression and the density profile of dark halos, and is expected to be insensitive to cosmological p...

Large and well defined variations exist between the distribution of mass and the light of stars on extragalactic scales. Mass concentrations in the range 10 − 10M⊙ manifest the most light per unit mass. Group halos in this range are typically the hosts of spiral and irregular galaxies with ongoing star formation. On average M/LB ∼ 90M⊙/L⊙ in these groups . More massive halos have less light per...

We develop a method to measure the probability, P (N ;M), of finding N galaxies in a dark-matter halo of mass M from the theoretically determined clustering properties of dark-matter halos and the observationally measured clustering properties of galaxies. Knowledge of this function and the distribution of the dark matter completely specifies all clustering properties of galaxies on scales larg...

On the one hand, the large scale structure of matter is arguably scale invariant, and, on the other hand, halos and voids are recognized as prominent features of that structure. To unify both approaches, we propose to model the dark matter distribution as a set of fractal distributions of halos of different kinds. This model relies on the concept of multifractal as the most general scaling dist...

A significant fraction of galaxy clusters exhibits cluster wide radio halos. We give a simple prediction of the local and higher redshift radio halo luminosity function (RHLF) on the basis of (i) an observed and a theoretical X-ray cluster luminosity function (XCLF) (ii) the observed radio–X-ray luminosity correlation (RXLC) of galaxy clusters with radio halos (iii) an assumed fraction of frh ≈...