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Related papers: Rates for Color Shifted Microlensing Events

200 papers

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

The current modelling of single microlensing light curves neglects the possibility that only a fraction of the light is due to the lensed star, the remaining being due to a close, unresolved blend, which may be related or unrelated to the…

Astrophysics · Physics 2009-10-30 Przemyslaw Wozniak , Bohdan Paczynski

At present, microlensing light curves from different telescopes and filters are photometrically aligned by fitting them to a common model. We present a second method based on photometry of common field stars. If two spectral responses are…

Earth and Planetary Astrophysics · Physics 2014-11-20 Andrew Gould , Subo Dong , David P. Bennett , Ian A. Bond , Andrzej Udalski , Szymon Kozlowski

We develop a new method to measure source proper motions in microlensing events, which can partially overcome problems due to blending. It takes advantage of the fact that the source position is known precisely from the microlensing event…

If a gravitational microlensing event is caused by a widely separated binary lens and the source approaches both lens components, the source flux is successively magnified by the individual lenses: double microlensing events. If events are…

Astrophysics · Physics 2009-11-07 Cheongho Han , Byeong-Gon Park , Wonyong Han , Young Woon Kang

We present the first detection of parallax effects in a gravitational microlensing event. Parallax in a gravitational microlensing event observed only from the Earth appears as a distortion of the lightcurve due to the motion of the Earth…

We present the photometry and theoretical models for a Galactic bulge microlensing event OGLE-2000-BUL-43. The event is very bright with I=13.54 mag, and has a very long time scale, t_E=156 days. The long time scale and its light curve…

Currently, gravitational microlensing survey experiments toward the Galactic bulge field utilize two different methods of minimizing blending effect for the accurate determination of the optical depth \tau. One is measuring \tau based on…

Astrophysics · Physics 2009-11-13 Cheongho Han

The biggest uncertainty in determining microlensing parameters comes from the blending of source star images because the current experiments are being carried out toward very dense star fields: the Galactic bulge and Magellanic Clouds. The…

Astrophysics · Physics 2016-08-30 Cheongho Han

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

In this paper, we investigate the color changes of gravitational microlensing events caused by the two different mechanisms of differential amplification for a limb-darkened extended source and blending. From this investigation, we find…

Astrophysics · Physics 2009-10-31 Cheongho Han , Seong-Hong Park , Jang-Hae Jeong

Perhaps as many as 30 parallax microlensing events are known, thanks to the efforts of the MACHO, OGLE, EROS and MOA experiments monitoring the bulge. Using Galactic models, we construct mock catalogues of microlensing light curves towards…

Astrophysics · Physics 2009-11-11 M. C. Smith , V. Belokurov , N. W. Evans , S. Mao , J. H. An

The uncertainty of the lens mass can be substantially reduced if it is determined from the lens proper motion obtained from astrometric measurements of the source image centroid shifts, $\vdelta\vtheta_c$, by using high precision…

Astrophysics · Physics 2007-05-23 Cheongho Han , Kyongae Chang

We show that at any given time, the Galactocentric black hole Sgr A* is expected to be microlensing N(lens)=1.7 bulge stars if the threshold of detectability of the fainter image is K(thr)=21, and about N(lens)=8 sources if K(thr)=23. The…

Astrophysics · Physics 2009-11-06 Julio Chaname , Andrew Gould , Jordi Miralda-Escude

In this work, we present the analysis of the binary microlensing event OGLE-2018-BLG-0022 that is detected toward the Galactic bulge field. The dense and continuous coverage with the high-quality photometry data from ground-based…

In order to understand the nature of the lenses that generate microlensing events, one would like to measure their mass, distance, and velocity. Unfortunately, current microlensing experiments measure only one parameter of the events, the…

Astrophysics · Physics 2009-10-28 B. Scott Gaudi , Andrew Gould

Observations of caustic-crossing galaxies at redshift $0.7<z<1$ show a wealth of transient events. Most of them are believed to be microlensing events of highly magnified stars. Earlier work predicted such events should be common near the…

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

Microlensing events are now regularly being detected by monitoring the flux of a large number of potential sources and measuring the combined magnification of the images. This phenomenon could also be detected directly from the…

Astrophysics · Physics 2009-10-28 Jordi Miralda-Escude