English
Related papers

Related papers: Astrometric microlensing

200 papers

Gravitational microlensing occurs when a foreground star happens to pass very close to our line of sight to a more distant background star. The foreground star acts as a lens, splitting the light from the source star into two images, which…

Earth and Planetary Astrophysics · Physics 2010-02-03 B. Scott Gaudi

In this paper, we investigate the effect of a wide binary companion of the lens on the astrometric behavior of Galactic gravitational microlensing events and compare it to the effect on the photometric behavior. We find that the wide binary…

Astrophysics · Physics 2007-05-23 Jin H. An , Cheongho Han

Context. Astrometric microlensing is an excellent tool to determine the mass of a stellar object. By measuring the astrometric shift of a background source star in combination with precise predictions of its unlensed position and of the…

Solar and Stellar Astrophysics · Physics 2018-07-25 J. Klüter , U. Bastian , M. Demleitner , J. Wambsganss

Interferometers from the ground and space will be able to resolve the two images in a microlensing event. This will at least partially lift the inherent degeneracy between physical parameters in microlensing events. To increase the…

Astrophysics · Physics 2016-08-30 N. J. Rattenbury , S. Mao

The luminosity variation of a stellar source due to the gravitational microlensing effect can be considered also if the light rays are defocused (instead of focused) toward the observer. In this case, we should detect a gap instead of a…

High-resolution N-body simulations of dark matter halos indicate that the Milky Way contains numerous subhalos. When a dark matter subhalo passes in front of a star, the light from that star will be deflected by gravitational lensing,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Adrienne L. Erickcek , Nicholas M. Law

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…

When a source star is microlensed by one stellar component of a widely separated binary stellar components, after finishing the lensing event, the event induced by the other binary star can be additionally detected. In this paper, we…

Solar and Stellar Astrophysics · Physics 2011-02-11 Sun-Ju Chung , Byeong-Gon Park , Yoon-Hyun Ryu , Andrew Humphrey

Gravitational microlensing is currently the only technique that helps study the Galactic distribution of planets as a function of distance from the Galactic center. The Galactic location of a lens system can be uniquely determined only when…

Earth and Planetary Astrophysics · Physics 2021-09-08 Naoki Koshimoto , David P. Bennett , Daisuke Suzuki , Ian A. Bond

We measure the astrometric shifts of the light centroids for the microlensing events in the OGLE-1 database. Of the 15 consistently detected events, 7 had significant shifts which we were able to measure with a fair degree of confidence.…

Astrophysics · Physics 2007-05-23 David M. Goldberg , Przemyslaw Wozniak

Microlensing events can be used to directly measure the masses of single field stars to a precision of $\sim$1-10\%. The majority of direct mass measurements for stellar and sub-stellar objects typically only come from observations of…

Solar and Stellar Astrophysics · Physics 2018-11-09 M. B. Nielsen , D. M. Bramich

Despite the suspected binarity for a significant fraction of Galactic lenses, the current photometric surveys detected binary microlensing events only for a small fraction of the total events. The detection efficiency is especially low for…

Astrophysics · Physics 2009-10-31 Cheongho Han

When there is more than one source of light along the line of sight to a gravitationally lensed object, the characteristics of the observed light curve are influenced by the presence of the light that is not lensed. In this paper we develop…

Astrophysics · Physics 2009-10-28 R. DiStefano , A. A. Esin

The simple physics of microlensing provides a well-understood tool with which to probe the atmospheres of distant stars in the Galaxy and Local Group with high magnification and resolution. Recent results in measuring stellar surface…

Astrophysics · Physics 2007-05-23 Penny D. Sackett

Gravitational microlensing surveys target very dense stellar fields in the local group. As a consequence the microlensed source stars are often blended with nearby unresolved stars. The presence of `blending' is a cause of major uncertainty…

Astrophysics · Physics 2009-11-13 Martin C. Smith , Przemyslaw Wozniak , Shude Mao , Takahiro Sumi

The phenomenon of microlensing has successfully been used to detect extrasolar planets. By observing characteristic, rare deviations in the gravitational microlensing light curve one can discover that a lens is a star--planet system. In…

Earth and Planetary Astrophysics · Physics 2014-04-15 Krzysztof Rybicki , Łukasz Wyrzykowski

Gravitational microlensing has proved to be a versatile astrophysical tool. Recently, the question of whether higher order relativistic corrections can influence the observable properties of microlensing has been addressed. This letter…

Astrophysics · Physics 2009-11-06 Geraint F. Lewis , X. Rosalind Wang

Context. Astrometric gravitational microlensing can be used to determine the mass of a single star (the lens) with an accuracy of a few percent. To do so, precise measurements of the angular separations between lens and background star with…

Instrumentation and Methods for Astrophysics · Physics 2020-08-26 J. Klüter , U. Bastian , J. Wambsganss

We present the first public code for the calculation of the astrometric centroid shift occurring during microlensing events. The computation is based on the contour integration scheme and covers single and binary lensing of finite sources…

Instrumentation and Methods for Astrophysics · Physics 2021-05-26 Valerio Bozza , Elahe Khalouei , Etienne Bachelet