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Related papers: MACHOs in dark matter haloes

200 papers

We present preliminary results of the analysis of 5 years of MACHO data on the Galactic bulge microlensing events with clump giants as sources. This class of events allows one to obtain robust conclusions because relatively bright clump…

Models of our galaxy based on dynamical observations predict a spheroid component much heavier than accounted for by direct measurements of star counts and high velocity stars. If, as first suggested by Caldwell and Ostriker, this…

Astrophysics · Physics 2010-11-30 G. F. Giudice , S. Mollerach , E. Roulet

Microlensing and pixel-lensing surveys play a fundamental role in the searches for galactic dark matter and in the study of the galactic structure. Recent observations suggest the presence of a population of old white dwarfs with high…

Astrophysics · Physics 2009-11-10 M. Hafizi , F. De Paolis , G. Ingrosso , A. A. Nucita

We investigate the effects of numerous dark matter subhalos in a galaxy-sized halo on the events of strong lensing, to assess their presence as expected from the cold dark matter scenario. Lens galaxies are represented by a smooth ellipsoid…

Astrophysics · Physics 2009-11-07 Masashi Chiba

The stellar mass - halo mass relation provides a strong basis for connecting galaxies to their host dark matter halos in both simulations and observations. Other observable information, such as the density of the local environment, can…

Astrophysics of Galaxies · Physics 2023-10-19 Haley Bowden , Peter Behroozi , Andrew Hearin

We explore the lowest mass limit that can be placed on the halo mass function in CDM using 28 strong gravitational lenses. For this purpose, we study an extreme model in which the halo mass function and mass-concentration relation follow…

The balance of evidence indicates that individual galaxies and groups or clusters of galaxies are embedded in enormous distributions of cold, weakly interacting dark matter. These dark matter 'halos' provide the scaffolding for all luminous…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-26 James E. Taylor

We investigate the dark halo lens mass function (MF) for a wide class of spheroidal non singular isothermal models comparing observed and observable microlensing quantities for MACHO observations towards LMC and taking into account the…

Astrophysics · Physics 2007-05-23 V. F. Cardone , R. de Ritis , A. A. Marino

The only microlensing events towards the Magellanic Clouds for which the location of the lens is strongly constrained are the two binary caustic crossing events. In at least one and possibly both cases, the lens lies at, or close to, the…

Astrophysics · Physics 2009-10-31 E. J. Kerins , N. W. Evans

In order to determine an upper bound for the mass of the massive compact halo objets (MACHOs) we use the halo binaries contained in a recent catalog (Allen \& Monroy-Rodr\'{\i}guez 2013). To dynamically model their interactions with massive…

Astrophysics of Galaxies · Physics 2015-06-22 Miguel A. Monroy-Rodríguez , Christine Allen

We examine the possibility that galactic halos are collisionless ensembles of scalar field ``massive compact halo objects'' (MACHOs). Using mass constraints from MACHO microlensing and from theoretical arguments on halos made up of massive…

Astrophysics · Physics 2022-11-08 Xavier Hernández , Tonatiuh Matos , Roberto A Sussman , Yosef Verbin

One of the biggest obstacles to our full understanding of the global dynamics in Milky Way and other spiral galaxies is uncertainty with respect to the form of baryonic dark matter in galactic haloes. Two basic forms discussed recently are…

Astrophysics · Physics 2007-05-23 Milan M. Cirkovic , Srdjan Samurovic , Vesna Milosevic-Zdjelar

I review proposals for explaining the current gravitational microlensing results from the EROS and MACHO surveys towards the Magellanic Clouds. Solutions involving massive compact halo objects (MACHOs), both baryonic and non-baryonic, as…

Astrophysics · Physics 2007-05-23 Eamonn Kerins

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)…

We use a hybrid approach that combines high-resolution simulations of the formation of a Milky Way-like halo with a semi-analytic model of galaxy formation to study the mass content of dwarf galaxies in the concordance $\Lambda$CDM…

Astrophysics · Physics 2009-06-16 Yang-Shyang Li , Amina Helmi , Gabriella De Lucia , Felix Stoehr

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…

In this paper we study the triaxial properties of dark matter haloes of a wide range of masses extracted from a set of cosmological N-body simulations. We measure the shape at different distances from the halo centre (characterised by…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-18 Giulia Despali , Carlo Giocoli , Mario Bonamigo , Marceau Limousin , Giuseppe Tormen

We report the detection of 45 candidate microlensing events in fields toward the Galactic bulge. These come from the analysis of 24 fields containing 12.6 million stars observed for 190 days in 1993. Many of these events are of extremely…

We present an analysis of the longest timescale microlensing events discovered by the MACHO Collaboration during a 7 year survey of the Galactic bulge. We find 6 events that exhibit very strong microlensing parallax signals due, in part, to…

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…