English
Related papers

Related papers: Microlensing by the Halo MACHOs with Spatially Var…

200 papers

(Short version) The nature and the location of the lenses discovered in the microlensing surveys done so far towards the LMC remain unclear. This contribution is comprised of two distinct parts. In the first part, motivated by these…

Astrophysics · Physics 2016-11-09 Ph. jetzer , A. Milsztajn , P. Tisserand

We describe a few recent microlensing results from the MACHO Collaboration. The aim of the MACHO Project was the identification and quantitative description of dark and luminous matter in the Milky Way using microlensing toward the…

We conduct gravitational microlensing experiments in a galaxy taken from a cosmological N-body simulation. Hypothetical observers measure the optical depth and event rate toward hypothetical LMCs and compare their results with model…

Astrophysics · Physics 2009-10-30 Lawrence M. Widrow , John Dubinski

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 mass function (MF) of isolated objects measured by microlensing consists of both a stellar and a planetary component. We compare the microlensing MFs of Gould et al (2022) and Sumi et al (2023) to other measurements of the MF. The…

Earth and Planetary Astrophysics · Physics 2025-03-17 Jennifer C. Yee , Scott J. Kenyon

We have searched for long duration microlensing events originating from intermediate mass Black Holes (BH) in the halo of the Milky Way, using archival data from EROS-2 and MACHO photometric surveys towards the Large Magellanic Cloud. We…

We discuss the tight interconnection between microlensing optical depths, flattening of dark haloes and low-to-intermediate redshift baryonic census. By analysing plots of the microlensing optical depth as a function of galactic coordinates…

Astrophysics · Physics 2009-10-31 Srdjan Samurovic , Milan M. Cirkovic , Vesna Milosevic-Zdjelar

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

Recent observations of microlensing events in the Large Magellanic Cloud by the MACHO and EROS collaborations suggest that an important fraction of the galactic halo is in form of Massive Astrophysical Compact Halo Objects (MACHOs) with…

High Energy Physics - Phenomenology · Physics 2007-05-23 F. De Paolis , G. Ingrosso , Ph. Jetzer , M. Roncadelli

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 investigate the implications of a bulk rotational component of the halo velocity distribution for MACHO mass estimates. We find that for a rotating halo to yield a MACHO mass estimate significantly below that of the standard spherical…

Astrophysics · Physics 2020-11-25 G. Gyuk , E. Gates

Traditional evidence for large amount of dark matter is based on dynamical consideration for systems with $ t_{dyn} \gg t_{obs} $. Recent observational and theoretical developments in gravitational lensing offer a much more robust…

Astrophysics · Physics 2009-10-22 Bohdan Paczyński

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

Foundations of standard theory of microlensing are described, namely we consider microlensing stars in Galactic bulge, the Magellanic Clouds or other nearby galaxies. We suppose that gravitational microlenses lie between an Earth observer…

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

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…

We consider a contribution of microlensing in X-ray variability of high-redshifted QSOs. Such an effect could be caused by stellar mass objects (SMO) located in a bulge or/and in a halo of this quasar as well as at cosmological distances…

Astrophysics · Physics 2009-11-10 A. F. Zakharov , L. C. Popovic , P. Jovanovic

The discovery of Massive Astrophysical Compact Halo Objects (MACHOs) in microlensing experiments makes it compelling to understand their physical nature, as well as their formation mechanism. Within the present uncertainties, brown dwarfs…

Astrophysics · Physics 2011-05-12 F. De Paolis , G. Ingrosso , Ph. Jetzer , M. Roncadelli

We investigate the possibility of lens mass determination for a caustic crossing microlensing event based on a space telescope observation. We demonstrate that the parallax due to the orbital motion of a space telescope causes a periodic…

Astrophysics · Physics 2009-10-31 Mareki Honma

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

Since the first discovery of microlensing events nearly two decades ago, gravitational microlensing has accumulated tens of TBytes of data and developed into a powerful astrophysical technique with diverse applications. The review starts…

Astrophysics of Galaxies · Physics 2015-06-05 Shude Mao