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Related papers: Microlensing results and the galactic models

200 papers

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

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…

Four microlensing collaborations are presently searching for compact matter in the Galaxy and all have detected possible candidates. Using the detection efficiencies recently published by the MACHO and OGLE collaborations, we present…

Astrophysics · Physics 2015-06-24 Eamonn J. Kerins

We estimate the fraction of mass that is composed of compact objects in gravitational lens galaxies. This study is based on microlensing measurements (obtained from the literature) of a sample of 29 quasar image pairs seen through 20 lens…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 E. Mediavilla , J. A. Munoz , E. Falco , V. Motta , E. Guerras , H. Canovas , C. Jean , A. Oscoz , A. M. Mosquera

We present a new analysis of the results of the EROS-2, OGLE-II, and OGLE-III microlensing campaigns towards the Small Magellanic Cloud (SMC). Through a statistical analysis we address the issue of the \emph{nature} of the reported…

Astrophysics of Galaxies · Physics 2013-09-27 S. Calchi Novati , S. Mirzoyan , Ph. Jetzer , G. Scarpetta

We combine the available astrometric and photometric data for the 1993 microlensing event MACHO-LMC-5 to measure the mass of the lens, M=0.097 +/- 0.016 Msun. This is the most precise direct mass measurement of a single star other than the…

Astrophysics · Physics 2009-11-10 Andrew Gould , David P. Bennett , David R. Alves

Characterizing the nature and spatial distribution of the lensing objects that produce the previously measured microlensing optical depth toward the Large Magellanic Cloud (LMC) remains an open problem. We present an appraisal of the…

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

Gravitational microlensing is a robust tool to detect and directly measure the abundance and mass of any kind of compact objects, either in our galaxy or in the extragalatic domain. On basis to generic, broadly applicable arguments, it is…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-27 E. Mediavilla , J. Jiménez-Vicente

Short version: Zaritsky and Lin (1997, ZL97) have recently presented observations which can be interpreted as evidence for an intervening stellar population along the line-of-sight to the LMC, at a distance of ~34 kpc. They suggest that it…

Astrophysics · Physics 2007-05-23 Eyal Maoz

The nature of the dark matter in the haloes of galaxies is one of the outstanding questions in astrophysics. All stellar candidates, until recently thought to be likely baryonic contributions to the Halo of our Galaxy, are shown to be ruled…

Astrophysics · Physics 2009-10-31 Katherine Freese , Brian D. Field , David S. Graff

For almost twenty years models of the Galaxy have included a dark halo responsible for supporting a substantial fraction of the local rotation velocity and a flat rotation curve at large distances. Estimates of the local halo density range…

Astrophysics · Physics 2011-09-29 E. Gates , G. Gyuk , M. Turner

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…

The discovery of the Sgr dwarf galaxy (Ibata, Gilmore, Irwin 1994) shows that the Galactic halo contains large clumps which are not full viralized. Stars in such a clump can lense a background extragalactic source. I use parameters of Sgr…

Astrophysics · Physics 2008-02-03 HongSheng Zhao

We present an analysis of the large set of microlensing events detected so far toward the Galactic center with the purpose of investigating whether some of the dark lenses are located in Galactic globular clusters. We find that in four…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-12 Philippe Jetzer

The MACHO project carries out regular photometric monitoring of millions of stars in the Magellanic Clouds and Galactic Bulge, to search for very rare gravitational microlensing events due to compact objects in the galactic halo and disk. A…

Microlensing observations towards M31 are a powerful tool for the study of the dark matter population in the form of MACHOs both in the Galaxy and the M31 halos, a still unresolved issue, as well as for the analysis of the characteristics…

The interpretation of microlensing results towards the Large Magellanic Cloud (LMC) still remains controversial. White dwarfs have been proposed to explain these results and, hence, to contribute significantly to the mass budget of our…

Astrophysics · Physics 2009-11-13 J. Camacho , S. Torres , J. Isern , L. G. Althaus , E. Garcia-Berro

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

Astrophysics · Physics 2009-10-31 Anne M Green

Basics of standard theory of microlensing are introduced. Results of microlensing observations toward Magellanic Clouds and relations with dark matter (DM) problem in our Galaxy are described. Pixel microlensing observations and recent…

Astrophysics · Physics 2007-05-23 Alexander F. Zakharov