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Related papers: The Local Halo Density

200 papers

We confirm and extend the recent finding that the central surface density r_0*rho_0 galaxy dark matter halos, where r_0 and rho_0 are the halo core radius and central density, is nearly constant and independent of galaxy luminosity. Based…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 F. Donato , G. Gentile , P. Salucci , C. Frigerio Martins , M. I. Wilkinson , G. Gilmore , E. K. Grebel , A. Koch , R. Wyse

We examine the claim by Oppenheimer et al. (2001) that the local halo density of white dwarfs is an order of magnitude higher than previously thought. As it stands, the observational data support the presence of a kinematically distinct…

Astrophysics · Physics 2017-08-23 L. V. E. Koopmans , R. D. Blandford

We construct a Galacto-Local Group rotation curve, combining the Galactic rotation curve with a diagram, where galacto-centric radial velocities of outer globular clusters and member galaxies of the Local Group are plotted against their…

Astrophysics · Physics 2015-05-13 Yoshiaki Sofue

It has been shown by Paczy\'nski that gravitational microlensing is potentially a useful method for detecting the dark constituents of the halo of our galaxy, if their mass lies in the approximate domain $10^{-6} < M/M_{\odot} < 10^{-1}$.…

Astrophysics · Physics 2008-02-03 Philippe Jetzer

Among the most fundamental properties of a dark matter halo is its density profile. Motivated by the recent proposal by Garc\'ia et al. [R. Garc\'ia et. al., MNRAS 521, 2464 (2023)] to define a dynamical halo as the collection of orbiting…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-02 Tristen Shields , Edgar M. Salazar , Eduardo Rozo , Aakanksha Adya , Calvin Osinga , Ze'ev Vladimir

The nature of the dark matter in the halo of our Galaxy is still largely unknown. The microlensing events found so far towards the Large Magellanic Cloud suggest that at most about 20% of the halo dark matter is in the form of MACHOs…

High Energy Physics - Phenomenology · Physics 2017-08-23 Philippe Jetzer

Using dark matter simulations we show how halo bias is determined by local density and not by halo mass. This is not totally surprising, as according to the peak-background split model, local density is the property that constraints bias at…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-08 Arnau Pujol , Kai Hoffmann , Noelia Jiménez , Enrique Gaztañaga

Recent observations of microlensing events in the Large Magellanic Cloud by the MACHO and EROS collaborations suggest that an important fraction of the galactic halo is in form of Massive Astrophysical Compact Halo Objects (MACHOs) with…

High Energy Physics - Phenomenology · Physics 2007-05-23 F. De Paolis , G. Ingrosso , Ph. Jetzer , M. Roncadelli

The most accurate way to get information on the mass of the MACHOs (Massive Astrophysical Compact Halo Objects) is to use the method of mass moments. For the microlensing events detected so far by the EROS and the MACHO collaborations in…

Astrophysics · Physics 2009-09-25 Philippe Jetzer , Eduard Masso

Rates for detection of weakly-interacting massive-particle (WIMP) dark matter are usually carried out assuming the Milky Way halo is an isothermal sphere. However, it is possible that our halo is not precisely spherical; it may have some…

High Energy Physics - Phenomenology · Physics 2010-11-30 Marc Kamionkowski , Ali Kinkhabwala

We discuss the tight interconnection between microlensing optical depths, flattening of dark haloes and low-to-intermediate redshift baryonic census. By analysing plots of the microlensing optical depth as a function of galactic coordinates…

Astrophysics · Physics 2009-10-31 Srdjan Samurovic , Milan M. Cirkovic , Vesna Milosevic-Zdjelar

We detect the weak gravitational lensing distortion of 450,000 background galaxies (20<R<23) by 790 foreground galaxies (R<18) selected from the Las Campanas Redshift Survey (LCRS). This is the first detection of weak lensing by field…

Astrophysics · Physics 2009-10-31 D. R. Smith , G. M. Bernstein , P. Fischer , R. M. Jarvis

The microlensing optical depth to Baade's Window constrains the minimum total mass in baryonic matter within the Solar circle to be greater than 3.9 x 10^{10} solar masses, assuming the inner Galaxy is barred with viewing angle of roughly…

Astrophysics · Physics 2009-11-07 J. J. Binney , N. W. Evans

We describe how a certain simple modification of general relativity, in which the local cosmological constant is allowed to depend on the space-time curvature, predicts the existence of halos of modified gravity surrounding…

General Relativity and Quantum Cosmology · Physics 2009-03-20 Kirill Krasnov , Yuri Shtanov

We derive the oblateness parameter q of the dark matter halo of a sample of gas rich, face-on disk galaxies. We have assumed that the halos are triaxial in shape but their axes in the disk plane (a and b) are equal, so that q=c/a measures…

Astrophysics of Galaxies · Physics 2023-03-29 Mousumi Das , Roger Ianjamasimanana , Stacy S. McGaugh , James Schombert , K. S. Dwarakanath

Recent observations of microlensing events in the Large Magellanic Cloud by the MACHO and EROS collaborations suggest that an important fraction of the galactic halo is in the form of Massive Halo Objects (MHO) with mass $\sim 0.1…

Astrophysics · Physics 2009-10-22 F. De Paolis , G. Ingrosso , Ph. Jetzer , M. Roncadelli

We report a series of high-resolution N-body simulations designed to examine the internal physical properties of dark matter halos. A total of fifteen halos, each represented by $\sim 1$ million particles within the virial radius, have been…

Astrophysics · Physics 2009-09-25 Y. P. Jing , Yasushi Suto

We report on a search for long duration microlensing events towards the Large Magellanic Cloud. We find none, and therefore put limits on the contribution of high mass objects to the Galactic dark matter. At 95% confidence level we exclude…

We present the first galaxy-galaxy weak lensing results using early data from the Canada-France-Hawaii Telescope Legacy Survey (CFHTLS). These results are based on ~22 sq. deg. of i' data. From this data, we estimate the average velocity…

(Abridged) Axisymmetric models of the Milky Way exhibit strong interrelations between the Galactic constants (R_0 and T_0), the stellar columndensity (S_*) and the shape of the dark matter (DM) halo. Here we present analytical relations…

Astrophysics · Physics 2009-11-06 R. P. Olling , M. R. Merrifield