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Related papers: Pixel Lensing Experiment toward the M31 Bulge

200 papers

It is estimated that a star brighter than visual magnitude 17 is undergoing a detectable gravitational microlensing event, somewhere on the sky, at any given time. It is assumed that both lenses and sources are normal stars drawn from a…

Astrophysics · Physics 2009-10-30 Robert J. Nemiroff

We study the statistics and properties of microlensing events that can be detected by the Transiting Exoplanet Survey Satellite(TESS) based on Monte Carlo simulations. We simulate potential microlensing events from a sample of the TESS…

Earth and Planetary Astrophysics · Physics 2024-08-27 Sedighe Sajadian , Atousa Kalantari , Hossein Fatheddin , Somayeh Khakpash

We investigate microlensing amplification of faint stars in the dense stellar cluster in the Galactic Center (GC) by the super-massive black hole (BH). Such events would appear very close to the position of the radio source SgrA*, which is…

Astrophysics · Physics 2009-10-31 Tal Alexander , Amiel Sternberg

Gravitational microlensing has been employed to identify massive halo objects by their amplification of distant sources; MACHO searches have studied event times $2 h \lesssim t_0 \lesssim 2 y$ corresponding masses in the range $10^{-6}…

General Relativity and Quantum Cosmology · Physics 2008-12-27 Paul H. Frampton

The MACHO collaboration has been carrying out Difference Image Analysis (DIA) since 1996 with the aim of increasing the sensitivity to the detection of gravitational microlensing. This is a preliminary report on the application of DIA to…

We estimate the detection efficiency of binary gravitational lensing events through the channel of high-magnification events. From this estimation, we find that binaries in the separations ranges of 0.1 < s < 10, 0.2 < s < 5, and 0.3 < s <…

Solar and Stellar Astrophysics · Physics 2014-11-20 Cheongho Han , Kyu-Ha Hwang

The gravitational fields of astrophysical bodies bend the light around them, creating multiple paths along which light from a distant source can arrive at Earth. Measuring the difference in photon arrival time along these different paths…

In this work, we study detecting free-floating planets (FFPs) by microlensing observations towards the Magellanic Clouds (MCs). In comparison to similar events toward the Galactic bulge, an FFP in the Galactic halo produces on average…

Earth and Planetary Astrophysics · Physics 2021-07-14 Sedighe Sajadian

We present the analysis of the binary-lens microlensing event OGLE-2017-BLG-0537. The light curve of the event exhibits two strong caustic-crossing spikes among which the second caustic crossing was resolved by high-cadence surveys. It is…

We investigate properties of Galactic microlensing events in which a stellar object is lensed by a neutron star. For an all-sky photometric microlensing survey, we determine the number of lensing events caused by $\sim10^{5}$…

Astrophysics of Galaxies · Physics 2015-07-03 Shi Dai , Martin C. Smith , Mengxiang Lin , Youling Yue , George Hobbs , Renxin Xu

Microlensing is a powerful technique to study the Galactic population of "dark" objects such as exoplanets both bound and unbound, brown dwarfs, low-luminosity stars, old white dwarfs, neutron stars, and almost the only way to study…

Simulations of planetary microlensing at high magnification that were carried out on a cluster computer are presented. It was found that the perturbations due to two-thirds of all planets occur in the time interval [-0.5t_FWHM, 0.5t_ FWHM]…

Astrophysics · Physics 2009-11-07 N. J. Rattenbury , I. A. Bond , J. Skuljan , P. C. M. Yock

We report the discovery of a short-duration microlensing candidate in the Northern field of the POINT-AGAPE pixel lensing survey towards M31. The full-width at half-maximum timescale is very short (tfwhm = 1.8 days) and the source star has…

Astrophysics · Physics 2007-05-23 Stephane Paulin-Henriksson

We discuss the potential of the gravitational microlensing method as a unique tool to detect unambiguous signals caused by intermediate-mass black holes in globular clusters. We select clusters near the line of sight to the Galactic Bulge…

Astrophysics of Galaxies · Physics 2016-06-15 N. Kains , D. M. Bramich , K. C. Sahu , A. Calamida

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

The only way to detect planets around stars at distances of several kpc is by (photometric or astrometric) microlensing observations. In this paper, we show that the capability of photometric microlensing extends to the detection of signals…

Astrophysics · Physics 2007-05-23 G. Covone , R. de Ritis , M. Dominik , A. A. Marino

The discoveries of 17 microlensing event candidates have been reported over the last year by three teams conducting unprecedented mass photometric searches in the direction of the Galactic bulge and the Magellanic Clouds. These include 10…

Astrophysics · Physics 2009-09-25 A. Udalski , M. Szymanski , J. Kaluzny , M. Kubiak , M. Mateo , W. Krzeminski , B. Paczynski

We present new optical long-slit data along 6 position angles of the bulge region of M31. We derive accurate stellar and gas kinematics reaching 5 arcmin from the center, where the disk light contribution is always less than 30%, and out to…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 R. P. Saglia , M. Fabricius , R. Bender , M. Montalto , C. -H. Lee , A. Riffeser , S. Seitz , L. Morganti , O. Gerhard , U. Hopp

We report the final analysis of a search for microlensing events in the direction of the Andromeda galaxy, which aimed to probe the MACHO composition of the M31 halo using data collected during the 1998-99 observational campaign at the MDM…

Gravitational microlensing depends primarily on the lens mass and presents a larger occurrence rate in crowded regions, which makes it the best tool to uncover the initial mass function (IMF) of low-mass stars in the Galactic bulge. The…