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The current searches for microlensing events towards the galactic bulge can be used to detect planets around the lensing stars. Their effect is a short-term modulation on the smooth lightcurve produced by the main lensing star. Current and…

Astrophysics · Physics 2015-06-24 Joachim Wambsganss

We use detailed numerical simulations and theoretical estimates to show that, if confirmed, the unusually brief microlensing events observed by Sahu et al. (2001) in the field of the globular cluster M22 might be explained as a result of…

Astrophysics · Physics 2009-11-07 R. de la Fuente Marcos , C. de la Fuente Marcos

A large number of microlensing events have been observed in the direction of the Galactic bulge, with a measured optical depth in the range 2 - 3 x 10^{-6}. It has been shown that most of these events are due to bulge stars being lensed by…

Astrophysics · Physics 2009-10-30 Vibhat Nair , Jordi Miralda-Escude

We investigate the gravitational lensing properties of dark matter halos with Burkert profiles. We derive an analytic expression for the lens equation and use it to compute the magnification, impact parameter and image separations for…

Astrophysics · Physics 2009-11-07 Yousin Park , Henry C. Ferguson

We have worked out simple analytical formulae that accurately approximate the relationship between the position of the source with respect to the lens center and the amplification of the images, hence the lens cross section, for realistic…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 A. Lapi , M. Negrello , J. Gonzalez-Nuevo , Z. -Y. Cai , G. De Zotti , L. Danese

We present an analysis of the light curves of 9.1 million stars observed during three seasons by EROS (Experience de Recherche d'Objets Sombres), in the Galactic plane away from the bulge. Seven stars exhibit luminosity variations…

Astrophysics · Physics 2012-08-27 EROS Collaboration

Modern surveys of gravitational microlensing events have progressed to detecting thousands per year. Surveys are capable of probing Galactic structure, stellar evolution, lens populations, black hole physics, and the nature of dark matter.…

We study heterogeneous quantities that efficiently cross-correlate the lensing information encoded in CMB polarization and large-scale structures recovered from weak lensing galaxy surveys. These quantities allow us to take advantage of the…

Astrophysics · Physics 2007-05-23 K. Benabed , F. Bernardeau , L. Van Waerbeke

Increasing evidences suggest that the Galactic halo is lumpy on kpc scales due to the accretion of at least a dozen small galaxies (LMC/SMC, Sgr, Fornax etc.). Faint stars in such lumpy structures can significant microlense a background…

Astrophysics · Physics 2009-10-30 HongSheng Zhao

Much interest has been generated recently by the ongoing MACHO, EROS and OGLE projects to identify gravitationally lensed stars from the Large Magellanic Cloud and Galactic bulge, and the positive identification of several events (Alcock et…

Astrophysics · Physics 2007-05-23 J. F. L. Simmons , J. P. Willis , A. Newsam

We provide a set of microlensing optical depth maps for M31. Optical depths towards Andromeda were calculated on the basis of a four component model of the lens and source populations: disk and bulge sources lensed by bulge, M31 halo and…

Astrophysics · Physics 2007-05-23 Geza Gyuk , Arlin Crotts

Microlensing promises to be a powerful tool for studying distant galaxies and quasars. As the data and models improve, there are systematic effects that need to be explored. Quasar continuum and broad-line regions may respond differently to…

Astrophysics · Physics 2008-11-26 Arthur B. Congdon , Charles R. Keeton , S. J. Osmer

The carbon, nitrogen, and oxygen abundances and trends in the bulge are discussed in the context of our recent analysis of these elements in an on-going project based on near-IR spectra (Ryde et al. 2009). We obtained these using the CRIRES…

Astrophysics of Galaxies · Physics 2015-05-14 N. Ryde

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 present preliminary results of the analysis of 5 years of MACHO data on the Galactic bulge microlensing events with clump giants as sources. In particular, we discuss: 1) the selection of `giant' events, 2) distribution of impact…

Occultation and microlensing are different limits of the same phenomena of one body passing in front of another body. We derive a general exact analytic expression which describes both microlensing and occultation in the case of spherical…

Astrophysics · Physics 2009-11-07 Eric Agol

Effects of macro-and microlensing on the spatial and temporal characteristics of images of remote sources, observed through the inner regions of lensing galaxies are discussed. A particular attention was given to the case, when microlenses,…

Astrophysics · Physics 2007-05-23 A. A. Minakov , V. G. Vakulik

This review summarizes some aspects of the central kiloparsec scale structure of galaxies, and in particular spiral galaxies, elliptical galaxies and merger remnants. The focus is on results from optical and near-IR imaging and…

Astrophysics · Physics 2007-05-23 Roeland P. van der Marel

We investigated the dependence of the optical depth $\tau$ of the microlensing events on model parameters of the Galactic halo. We only consider Galactic mass models in which the rotation curve inside the Sun is compatible with the…

Astrophysics · Physics 2015-06-24 Yukitoshi Kan-ya , Ryoichi Nishi , Takashi Nakamura

In this paper we model the vertical structure of mass distribution of the Milky Way galaxy in the framework of a finite-width global disk model. Assuming the Galactic rotation curve only, we test inside the solar orbit the predictions of…

Astrophysics of Galaxies · Physics 2014-06-23 Joanna Jałocha , Szymon Sikora , Łukasz Bratek , Marek Kutschera
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