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Related papers: Optimal Microlensing Observations

200 papers

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

We present here an analysis of the light curves of 5.3 million stars in the Small Magellanic Cloud observed by EROS (Exp\'erience de Recherche d'Objets Sombres). One star exhibits a variation that is best interpreted as due to gravitational…

Astrophysics · Physics 2007-05-23 EROS collaboration , N. Palanque-Delabrouille et al

The detection of microlensing events from stars in the Large Magellanic Cloud and in the Galactic bulge raise important constraints on the distribution of dark matter and on galactic structure, although some events may be due to a new type…

Astrophysics · Physics 2020-11-25 David Valls-Gabaud

After a decade of gravitational microlensing experiments, a dozen of microlensing candidates in the direction of the stars of the Large Magellanic Cloud (LMC) have been detected by the EROS and MACHO groups. Recently it was shown that the…

Astrophysics · Physics 2009-11-10 Sohrab Rahvar

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

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…

The EROS-2 project was designed to test the hypothesis that massive compact halo objects (the so-called ``machos'') could be a major component of the dark matter halo of the Milky Way galaxy. To this end, EROS-2 monitored over 6.7 years…

Extreme microlensing events, defined as events with maximum magnification $A_\max\gsim 200$ are a potentially powerful probe of the mass spectrum and spatial distribution of objects along lines of sight toward the Galactic bulge. About 75…

Astrophysics · Physics 2007-05-23 Andrew Gould

A non-parametric statistical model is constructed to directly relate The distribution of observed microlens timescales to that of the mass Function of the population from which the lenses are drawn, corrected For observational selection…

Astrophysics · Physics 2007-05-23 William D. Heacox

More than a dozen microlensing events have been detected so far towards the LMC and 2 towards the SMC. If all the lenses are in the Galactic halo, both the LMC and the SMC events are expected to have similar time scales. However, the first…

Astrophysics · Physics 2009-10-31 Kailash C. Sahu , M. S. Sahu

Studies of gravitational microlensing effects require the estimation of their detection efficiency as soon as one wants to quantify the massive compact objects along the line of sight of source targets. This is particularly important for…

Astrophysics of Galaxies · Physics 2023-10-11 Tristan Blaineau , Marc Moniez

(Abridged) A close scrutiny of the microlensing results towards the Magellanic clouds reveals that the stars within the Magellanic clouds are major contributors as lenses, and the contribution of MACHOs to dark matter is 0 to 5%. The…

Astrophysics · Physics 2007-05-23 Kailash C. Sahu

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

Although a decade of microlensing searches towards the Large Magellanic Cloud (LMC) has detected 13-25 possible microlensing events, the nature and the location of the lenses, being either halo machos or LMC stars, remains a subject of…

Astrophysics · Physics 2009-11-07 HongSheng Zhao , Rodrigo Ibata , Geraint Lewis , Mike Irwin

By monitoring $10^6$ quasars one could search for lensing by stars and Massive Compact Halo Objects (Machos) out to redshifts $z\sim 4$. If Machos have a present cosmological density $\Omega_{L,0}=1\%$, then the expected event rate is…

Astrophysics · Physics 2009-10-28 Andrew Gould

Microlensing has a unique advantage for detecting dark objects in the Milky Way, such as free-floating planets, neutron stars, and stellar-mass black holes. Most microlensing surveys focus on the Galactic bulge, where higher stellar density…

Astrophysics of Galaxies · Physics 2024-11-11 Ruocheng Zhai , Antonio C. Rodriguez , Shude Mao , Casey Y. Lam , Eric C. Bellm , Josiah Purdum , Frank J. Masci , Avery Wold

Augmenting the \emph{WFIRST} microlensing campaigns with intensive observations from a ground-based network of wide-field survey telescopes would have several major advantages. First, it would enable full two-dimensional (2-D) vector…

Earth and Planetary Astrophysics · Physics 2017-01-18 Wei Zhu , Andrew Gould

While microlensing is very rare, occurring on average once per million stars observed, current and near-future surveys are coming online with the capability of providing photometry of almost the entire visible sky to depths up to R ~ 22 mag…

Instrumentation and Methods for Astrophysics · Physics 2020-04-30 D. Godines , E. Bachelet , G. Narayan , R. A. Street

It has been proposed that the Galaxy might contain a population of cold clouds in numbers sufficient to account for a substantial fraction of the total mass of the Galaxy. These clouds would have masses of the order of 10^{-3} Solar mass…

Astrophysics · Physics 2009-10-31 Roman R. Rafikov , Bruce T. Draine

After a decade of gravitational microlensing experiments, 13 to 17 events by MACHO (depending on quality) and two events by EROS have been detected. All of those have been observed in the direction of Large Magellanic Cloud. We use Evans…

Astrophysics · Physics 2009-11-07 Sohrab Rahvar