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Related papers: What are MACHOs? Interpreting LMC microlensing

200 papers

In the third part of the series presenting the Optical Gravitational Lensing Experiment (OGLE) microlensing studies of the dark matter halo compact objects (MACHOs) we describe results of the OGLE-III monitoring of the Large Magellanic…

Cosmological nucleosynthesis calculations imply that there should be both non-baryonic and baryonic dark matter. Recent data suggest that some of the non-baryonic dark matter must be "hot" (i.e. massive neutrinos) and there may also be…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Bernard Carr

We explore the connection between galaxies and dark matter halos in the Milky Way (MW) and quantify the implications on properties of the dark matter particle and the phenomenology of low-mass galaxy formation. This is done through a…

Astrophysics of Galaxies · Physics 2018-02-07 Prashin Jethwa , Denis Erkal , Vasily Belokurov

We study the prospects for the current microlensing searches, which have recently discovered several candidates, to yield useful information about the flattening of the Galaxy dark matter halo. Models of HI warps and N-body simulations of…

Astrophysics · Physics 2009-10-22 Joshua A. Frieman , Román Scoccimarro

We present Hubble Space Telescope (HST) WFPC2 photometry of 13 microlensed source stars from the 5.7 year Large Magellanic Cloud (LMC) survey conducted by the MACHO Project. The microlensing source stars are identified by deriving accurate…

The simplest interpretation of the microlensing events observed towards the Large Magellanic Cloud is that approximately half of the mass of the Milky Way halo is in the form of MAssive Compact Halo Objects with $M \sim 0.5 M_{\odot}$. This…

Astrophysics · Physics 2007-05-23 Anne M Green

If the halo of the lensing galaxy 0957+561 is made of massive compact objects (MACHOs), they must affect the lightcurves of the quasar images Q0957+561 A and B differently. We search for this microlensing effect in the double quasar by…

In a recent series of three papers, Belokurov, Evans, and Le Du, and Evans and Belokurov, reanalysed the MACHO collaboration data and gave alternative sets of microlensing events and an alternative optical depth to microlensing toward the…

Astrophysics · Physics 2009-11-10 Kim Griest , Christian L. Thomas

Recent interest in primordial black holes as a possible dark matter candidate has motivated the reanalysis of previous methods for constraining massive astrophysical compact objects in the Milky Way halo and beyond. In order to derive these…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-27 Josh Calcino , Juan Garcia-Bellido , Tamara M. Davis

The MACHO Collaboration's search for baryonic dark matter via its gravitational microlensing signature has generated a massive database of time ordered photometry of millions of stars in the LMC and the bulge of the Milky Way. The search's…

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

We use cosmological hydrodynamical simulations of the APOSTLE project along with high-quality rotation curve observations to examine the fraction of baryons in {\Lambda}CDM haloes that collect into galaxies. This 'galaxy formation…

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 a previous study it was proposed that the Galactic dark matter being detected by gravitational microlensing experiments such as MACHO may reside in a population of dim halo globular clusters comprising mostly or entirely low-mass stars…

Astrophysics · Physics 2008-02-03 E. J. Kerins

We discuss whether the Gaussian is a reasonable approximation of the velocity distribution of stellar systems that are not spherically distributed. By using a non-Gaussian velocity distribution to describe the sources in the Large…

Astrophysics of Galaxies · Physics 2012-01-10 Luigi Mancini

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

We propose an observational test that can break the degeneracy of two main classes of microlensing models to the Magellanic Clouds: (a) the lenses are located in the Galactic halo, and (b) the lenses are located in the LMC disk. The source…

Astrophysics · Physics 2009-10-31 HongSheng Zhao

We present a schematic model for the formation of baryonic galactic halos and hot gas in the Local Group and the intergalactic medium. We follow the dynamics, chemical evolution, heat flow and gas flows of a hierarchy of scales, including:…

Astrophysics · Physics 2009-10-28 Brian D. Fields , Grant J. Mathews , David N. Schramm

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

Lensing flux-ratio anomalies are most likely caused by gravitational lensing by small-scale dark matter structures. These anomalies offer the prospect of testing a fundamental prediction of the cold dark matter (CDM) cosmological model: the…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-20 D. D. Xu , Dominique Sluse , Liang Gao , Jie Wang , Carlos Frenk , Shude Mao , Peter Schneider