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Related papers: The Local Halo Density

200 papers

Techniques for inferring the radial and geometric form of dark matter halos and the results they have produced to date are reviewed. Dark halos appear to extend to at least ~50 kpc with total enclosed masses that rise linearly with radius…

Astrophysics · Physics 2007-05-23 Penny D. Sackett

The measurements of the possible gravitational microlensing events are analysed with a simple yet accurate disc--halo model of the Milky Way Galaxy. This comprises a luminous exponential disc embedded in a flattened dark matter halo with…

Astrophysics · Physics 2016-06-08 N. W. Evans , J. Jijina

We review the various techniques used to constrain the Galactic halo mass profile for radii > 20 kpc with particular emphasis on identifying a self-consistent halo model and resolving the apparent discrepancies present in the literature on…

Astrophysics · Physics 2007-05-23 Dennis Zaritsky

Paczy\'nski (1986) suggested that ``dark" objects in the halo of our Galaxy could enhance the luminosity of foreground stars, acting as gravitational microlenses. Such events has been recently reported by different collaborations. We assume…

Astrophysics · Physics 2007-05-23 Sergio Campana

Recent determination of the outer rotation curve of the Galaxy suggests that the total Galactic mass is likely to concentrate into a region of radius $\sim2R_0$. If this finding is correct, the previously estimated optical depth of…

Astrophysics · Physics 2016-08-30 Zong-Hong Zhu , Xiang-Ping Wu

We propose a heuristic model that displays the main features of realistic theories for galaxy bias. We show that the low-order clustering statistics of the dark-matter distribution depend almost entirely on the locations and density…

Astrophysics · Physics 2011-05-05 J. A. Peacock , R. E. Smith

A sample of 11 thousand galaxies with radial velocities V_ LG < 3500 km/s is used to study the features of the local distribution of luminous (stellar) and dark matter within a sphere of radius of around 50 Mpc around us. The average…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 I. D. Karachentsev

If the Universe has a significant baryonic dark component in the form of compact objects in galaxy halos (machos), then there is a minute chance (about $10^{-7}$) that one of the Galactic machos passes sufficiently close to our line of…

Astrophysics · Physics 2009-10-31 HongSheng Zhao

The detection of microlensing has opened the way for the development of new methods in galactic astronomy. This series of papers investigates what microlensing can teach us about the structure and shape of the dark halo. In this paper we…

We examine the properties of dark matter halos within a rich galaxy cluster using a high resolution simulation that captures the cosmological context of a cold dark matter universe. The mass and force resolution permit the resolution of 150…

Astrophysics · Physics 2009-10-30 Sebastiano Ghigna , Ben Moore , Fabio Governato , George Lake , Thomas Quinn , Joachim Stadel

We use high-quality optical rotation curves of 9 low-luminosity disk galaxies to obtain the velocity profile of the surrounding dark matter halos. We find that they increase linearly with radius at least out to the stellar disk edge,…

Astrophysics · Physics 2009-10-31 A. Borriello , P. Salucci

We present the recent robust determination of the value of the Dark Matter density at the Sun's location ($\rho_\odot$) with a technique that does not rely on a global mass-modeling of the Galaxy. The method is based on the local equation…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-18 Fabrizio Nesti , Paolo Salucci

We perform a series of high-resolution N-body simulations designed to examine the density profiles of dark matter halos. From 12 simulated halos ranging the mass of $2\times10^{12}\sim 5\times10^{14} h^{-1}{\rm M_\odot}$ (represented by…

Astrophysics · Physics 2009-10-31 Y. P. Jing , Yasushi Suto

We present a maximum-likelihood weak lensing analysis of the mass distribution in optically selected spectroscopic Galaxy Groups (G$^3$Cv5) in the Galaxy And Mass Assembly (GAMA) survey, using background Sloan Digital Sky Survey (SDSS)…

Microlensing has established itself as a powerful new method for the detection of baryonic dark matter in the Galaxy. The theory of microlensing is sketched and its similarity with the optical effect of twinkling is explained. The bulk of…

Astrophysics · Physics 2007-05-23 Wyn Evans

We present the results of a study of weak lensing by galaxies based on 45.5 deg$^2$ of $R_C$ band imaging data from the Red-Sequence Cluster Survey (RCS). We present the first weak lensing detection of the flattening of galaxy dark matter…

Astrophysics · Physics 2008-11-26 Henk Hoekstra , Howard K. C. Yee , Michael D. Gladders

We present a novel study on the problem of constructing mass models for the Milky Way, concentrating on features regarding the dark matter halo component. We have considered a variegated sample of dynamical observables for the Galaxy,…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Riccardo Catena , Piero Ullio

We use numerical simulations to examine the substructure within galactic and cluster mass halos that form within a hierarchical universe. Clusters are easily reproduced with a steep mass spectrum of thousands of substructure clumps that…

Observations of multiple-image gravitational lens systems suggest that the projected mass distributions of galaxy haloes may contain substantial inhomogeneities. The fraction of the halo mass in dense substructure is still highly uncertain,…

Astrophysics · Physics 2009-11-10 James E. Taylor , Arif Babul

Observations show that about the 20% of the Universe is composed by invisible (dark) matter (DM), for which many candidates have been proposed. In particular, the anomalous behavior of rotational curves of galaxies (i.e. the flattening at…

Cosmology and Nongalactic Astrophysics · Physics 2009-05-19 Nicola Rossi