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Related papers: Microlensing By a Prolate All-Macho Halo

200 papers

Observations show that the underlying rotation curves at intermediate radii in spiral and low-surface brightness galaxies are nearly universal. Further, in these same galaxies, the product of the central density and the core radius…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 F. D. A. Hartwick

Recently obtained kinematic data has shown that the Large Magellanic Cloud (LMC) possesses an old stellar halo. In order to further characterize the properties of this halo, parametric King models are fit to the surface density of RR Lyrae…

Astrophysics · Physics 2009-11-10 David R. Alves

Simulations of cold dark matter make robust predictions about the slope and normalization of the dark matter halo and subhalo mass functions on small scales. Recent observational advances utilizing strong gravitational lensing have…

Astrophysics of Galaxies · Physics 2020-02-12 Andrew J. Benson

We performed an extended analysis of the parameter space for the interaction of the Magellanic System with the Milky Way (MW). The varied parameters cover the phase space parameters, the masses, the structure, and the orientation of both…

Astrophysics · Physics 2009-11-11 A. Ruzicka , J. Palous , Ch. Theis

We present microlensing calculations for a Galactic model based on Han & Gould (2003), which is empirically normalised by star counts. We find good agreement between this model and data recently published by the MACHO and OGLE…

Astrophysics · Physics 2009-11-13 Alexander Wood , Shude Mao

Using deep images from the Hyper Suprime-Cam (HSC) survey and taking advantage of its unprecedented weak lensing capabilities, we reveal a remarkably tight connection between the stellar mass distribution of massive central galaxies and…

We provide a set of microlensing event rate maps for M31, the Andromeda Galaxy. Rates for M31 microlensing were calculated on the basis of a four component model of the lens and source populations: disk and bulge sources lensed by bulge,…

Astrophysics · Physics 2009-11-07 Edward A. Baltz , Geza Gyuk , Arlin Crotts

The shapes of dark halos (e.g. spherical, oblate or triaxial) provide important clues to the formation history of the halos, to their baryon content and to the nature of the dark matter. The halo shapes also influence the dynamics of the…

Astrophysics · Physics 2016-08-30 Hans-Walter Rix , Max-Planck- Inst. fuer Astrophysik

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 conduct gravitational microlensing experiments in a galaxy taken from a cosmological N-body simulation. Hypothetical observers measure the optical depth and event rate toward hypothetical LMCs and compare their results with model…

Astrophysics · Physics 2009-10-30 Lawrence M. Widrow , John Dubinski

This paper reviews the constraints that can be placed on the shapes of disk galaxies' dark halos using the distribution and kinematics of atomic hydrogen. These data indicate that dark halos are close to axisymmetric, with their axes of…

Astrophysics · Physics 2017-08-23 M. R. Merrifield

Cosmological models in which dark matter consists of cold elementary particles predict that the dark halo population should extend to masses many orders of magnitude below those at which galaxies can form. Here we report a cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-23 Jie Wang , Sownak Bose , Carlos S. Frenk , Liang Gao , Adrian Jenkins , Volker Springel , Simon D. M. White

Collisionless Dark Matter Only (DMO) structure formation simulations predict that Dark Matter (DM) haloes are prolate in their centres and triaxial towards their outskirts. The addition of gas condensation transforms the central DM shape to…

The evolution of chaotic motion in a galactic dynamical model with a disk, a dense nucleus and a flat biaxial dark halo component is investigated. Two cases are studied: (i) the case where the halo component is oblate and (ii) the case…

Astrophysics of Galaxies · Physics 2012-04-04 Nicolaos D. Caranicolas , Euaggelos E. Zotos

The nature and the location of the lenses discovered in the microlensing surveys done so far towards the LMC remain unclear. Motivated by these questions we computed the optical depth for the different intervening populations and the number…

Astrophysics · Physics 2007-05-23 Philippe Jetzer

Galaxy-galaxy strong gravitational lenses have become a popular probe of dark matter (DM) by providing a window into structure formation on the smallest scales. In particular, the convergence power spectrum of subhalos within lensing…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-25 Atınç Çağan Şengül , Arthur Tsang , Ana Diaz Rivero , Cora Dvorkin , Hong-Ming Zhu , Uroš Seljak

We investigate the possibility of determining whether microlensing objects towards the Large Magellanic Cloud (LMC) are in a Galactic thick disc, or are in a Galactic halo, by using parallax measurements with an Earth-radius scale baseline.…

Astrophysics · Physics 2009-11-07 T. Sumi , Y. Kan-ya

We study the efficiency of numerically simulated galaxy clusters for producing strong gravitational lensing events in different dark-energy cosmologies with constant and time-variable equation of state and we compare it with ``standard''…

It has been revealed using microlensing that a considerable part, possibly more than half, of the dark matter in the halo of our Galaxy consists of objects with a mass spectrum ranging from 0.05 to 0.8 of the solar mass. What is the nature…

Astrophysics · Physics 2007-05-23 A. V. Gurevich , K. P. Zybin , V. A. Sirota

In this proceeding, we briefly review three recent results. First, we show that halos formed in simulations with gas cooling are significantly rounder than halos formed in dissipationless $N$-body simulations. The increase in principle axis…

Astrophysics · Physics 2016-11-03 Andrew R. Zentner , Savvas M. Koushiappas , Stelios Kazantzidis