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Related papers: Microlensing towards the Large Magellanic Cloud

200 papers

I review recent results from gravitational microlensing surveys of the Large Magellanic Cloud. The combined microlensing optical depth of the MACHO and EROS-1 surveys is tau_LMC = 2.1{+1.3/-0.8}* 10^{-7} which is substantially larger than…

Astrophysics · Physics 2009-10-30 David Bennett

All of the proposed explanations for the microlensing events observed towards the LMC have difficulties. One of these proposed explanations, LMC self-lensing, which invokes ordinary LMC stars as the long sought-after lenses, has recently…

Astrophysics · Physics 2008-11-26 G. Gyuk , N. Dalal , K. Griest

EROS has been monitoring few million stars in the Magellanic clouds, as well as toward the Galactic bulge and spiral arms since 1996, to search for microlensing events. In this paper, we present briefly the EROS setup and scientific program…

Astrophysics · Physics 2007-05-23 R. Ansari

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…

A new type of gravitational microlensing experiment toward a field where stars are not resolved is being developed observationally and theoretically: pixel lensing. When the experiment is carried out toward the M31 bulge area, events may be…

Astrophysics · Physics 2009-10-28 Cheongho Han , Andrew Gould

We present the results of the EROS2 search for the hidden galactic matter of the halo through the gravitational microlensing of stars in the Magellanic clouds. Microlensing was also searched for and found in the Milky-Way plane, where…

Astrophysics of Galaxies · Physics 2009-01-21 M. Moniez

A simple interpretation of the more than dozen microlensing events seen in the direction of the LMC is a halo population of MACHOs which accounts for about half of the mass of the Galaxy. Such an interpretation is not without its problems,…

Astrophysics · Physics 2009-10-30 Evalyn I. Gates , Geza Gyuk , Gilbert P. Holder , Michael S. Turner

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 carry on a new analysis of the sample of MACHO microlensing candidates towards the LMC. Our main purpose is to determine the lens population to which the events may belong. We give particular emphasis to the possibility of characterizing…

Astrophysics · Physics 2009-11-11 S. Calchi Novati , F. De Luca , Ph. Jetzer , G. Scarpetta

We combine new results from the search for microlensing towards the Large Magellanic Cloud (LMC) by EROS2 (Experience de Recherche d'Objets Sombres) with limits previously reported by EROS1 and EROS2 towards both Magellanic Clouds. The…

Astrophysics · Physics 2007-05-23 T. Lasserre , EROS Collaboration

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

There are lines of evidence suggesting that some of the observed microlensing events in the direction of the Large Magellanic Cloud (LMC) are caused by ordinary star lenses as opposed to dark Machos in the Galactic halo. Efficient lensing…

Astrophysics · Physics 2009-10-31 HongSheng Zhao , David Graff , Puragra Guhathakurta

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…

Zhao has proposed that the microlensing events observed toward the Large Magellanic Cloud (LMC) could be due to faint stars in a dwarf galaxy or tidal debris lying along the line of sight to the LMC. Zaritsky & Lin claim to have detected…

Astrophysics · Physics 2007-05-23 Andrew Gould

The primary goal of this paper is to provide the evidence that can either prove or falsify the hypothesis that dark matter in the Galactic halo can clump into stellar-mass compact objects. If such objects existed, they would act as lenses…

We discuss the implications of the more than 50 microlensing events seen by the EROS, MACHO, and OGLE collaborations for the composition of the halo of our galaxy. The event rates indicate that the halo mass fraction in MACHO's is less than…

Astrophysics · Physics 2009-10-22 Evalyn I. Gates , Geza Gyuk , Michael S. Turner

We calculate the optical depth and the number of events due to gravitational microlensing towards the Galactic bulge, the spiral arm directions $\gamma$ Scutum, $\beta$ Scutum, $\gamma$ Normae, $\vartheta$ Muscae and some dwarf galaxies in…

Astrophysics · Physics 2007-05-23 Lukas Grenacher , Philippe Jetzer , Marcus Strässle , Francesco De Paolis

(Abridged version): The optical depth is widely used in Galactic microlensing studies as a means to determine the density of MACHOs, since in theory it depends only upon their spatial distribution and is therefore less model-dependent than…

Astrophysics · Physics 2009-10-30 E. J. Kerins

We present previously unpublished photometry of three Large Magellanic Cloud (LMC) microlensing events and show that the new photometry confirms the microlensing interpretation of these events. These events were discovered by the MACHO…

Astrophysics · Physics 2009-11-10 David P. Bennett , Andrew C. Becker , Austin Tomaney

Using eight dark matter haloes extracted from fully-self consistent cosmological N-body simulations, we perform microlensing experiments. A hypothetical observer is placed at a distance of 8.5 kpc from the centre of the halo measuring…

Astrophysics · Physics 2009-11-11 Janne Holopainen , Chris Flynn , Alexander Knebe , Stuart P. Gill , Brad K. Gibson
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