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Related papers: Astrometric microlensing

200 papers

We identify stars with large proper motions that are potential candidates for the astrometric microlensing effect during the Gaia mission i.e. between 2012 and 2019. The effect allows a precise measurement of the mass of a single star that…

Astrophysics of Galaxies · Physics 2012-01-20 Svea Proft , Markus Demleitner , Joachim Wambsganss

Using the astrometry of microlensing events we study the effect of angular momentum as compared to that of the parallax. For a rotating lens it is shown that the effect of the angular momentum deviates the center of images from that in the…

Astrophysics · Physics 2007-05-23 Habib Ebrahimnejad Rahbari , Mohammad Nouri-Zonoz , Sohrab Rahvar

In this article we review the astrophysical application of gravitational microlensing. After introducing the history of gravitational lensing, we present the key equations and concept of microlensing. The most frequent microlensing events…

Instrumentation and Methods for Astrophysics · Physics 2016-03-21 Sohrab Rahvar

Massive galactic lenses with large Einstein Radii should cause a measurable astrometric microlensing effect, i.e. the light centroid shift due to the motion of the two images. Such a shift in the position of a background star due to…

Solar and Stellar Astrophysics · Physics 2022-10-26 Maja Jabłońska , Łukasz Wyrzykowski , Krzysztof A. Rybicki , Katarzyna Kruszyńska , Zofia Kaczmarek , Zephyr Penoyre

The aim of this paper is to study the astrometric trajectory of microlensing events with an extended lens and/or source. We consider not only a dark lens but also a luminous lens as well. We find that the discontinuous finite-lens…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 C. -H. Lee , S. Seitz , A. Riffeser , R. Bender

The longest microlensing events provide enough information to estimate the mass and distance of the lens. Among hundreds of millions of stars which were monitored for many years by the OGLE project we selected those with clear parallax…

Solar and Stellar Astrophysics · Physics 2016-01-13 Łukasz Wyrzykowski , Zuzanna Kostrzewa-Rutkowska , Krzysztof Rybicki

Gravitational microlensing of quasars by stars in external galaxies can introduce fluctuations in the centroid of the ``point-like'' macro--images. The induced shifts are extremely small, on micro--arcsecond scales, below the limits of…

Astrophysics · Physics 2009-10-30 Geraint F. Lewis , Rodrigo A. Ibata

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

If a source star is gravitationally microlensed by a multiple lens system, the resulting light curve can have significant deviations from the standard form of a single lens event. The chance to produce significant deviations becomes…

Astrophysics · Physics 2009-11-07 Cheongho Han

The relative transverse velocity of a lens with respect to the source star in gravitational lensing results in a frequency shift in the light rays passing by a lens. We propose using this relativistic effect for measuring the relative…

Astrophysics of Galaxies · Physics 2020-01-08 Sohrab Rahvar

Astrometric microlensing is a unique tool to measure stellar masses. It allows us to determine the mass of the lensing star with an accuracy of a few per cent. In this paper, we update, extend, and refine our predictions of…

Solar and Stellar Astrophysics · Physics 2022-03-30 Jonas Klüter , Ulrich Bastian , Markus Demleitner , Joachim Wambsganss

Over the past decade, microlensing has developed into a powerful tool to study stellar astrophysics, especially stellar atmospheres, stellar masses, and binarity. I review this progress. Stellar atmospheres can be probed whenever the source…

Astrophysics · Physics 2016-08-30 Andrew Gould

An extra-solar planet can be detected by microlensing because the planet can perturb the smooth lensing light curve created by the primary lens. However, it was shown by Gaudi that a subset of binary-source events can produce light curves…

Astrophysics · Physics 2009-11-06 Cheongho Han

We discuss the gravitational lensing of gravitational wave signals from coalescing binaries. We delineate the regime where wave effects are significant from the regime where geometric limit can be used. Further, we focus on the effect of…

Cosmology and Nongalactic Astrophysics · Physics 2019-12-18 Ashish Kumar Meena , J S Bagla

We give an assessment of the significance of various known effects which may produce genuine fluctuations of star positions comparable to or larger than Gaia's measurement noise, and which thus may limit the ultimately reachable precision…

Astrophysics · Physics 2007-05-23 U. Bastian , H. Hefele

The effect of stars on the lensing properties of the supermassive black hole in the Galactic Center is similar to the effect of planets on microlensing by a star. We show that the dense stellar cluster around SgrA* increases by factors of a…

Astrophysics · Physics 2009-10-31 Tal Alexander , Abraham Loeb

In recent years, gravitational lensing has been used as a means to detect substructure in galaxy-sized halos, via anomalous flux ratios in quadruply-imaged lenses. In addition to causing anomalous flux ratios, substructure may also perturb…

Astrophysics · Physics 2011-02-11 Jacqueline Chen , Eduardo Rozo , Neal Dalal , James E. Taylor

We propose and discuss a new experimental approach to measure the centroid shift induced by gravitational microlensing in the images of lensed quasars (astrometric microlensing). Our strategy is based on taking the photocenter of a region…

Astrophysics of Galaxies · Physics 2024-06-18 R. Forés-Toribio , E. Mediavilla , J. A. Muñoz , J. Jiménez-Vicente , C. Fian , C. del Burgo

If stars at the lower end of the main sequence are responsible for the microlensing events observed in the Galactic bulge, then light from the lensing star contributes to the observed brightness. The background and lensing stars generally…

Astrophysics · Physics 2009-10-22 Marc Kamionkowski

We introduce a new method of searching for and characterizing extra-solar planets. We show that by monitoring the center-of-light motion of microlensing alerts using the next generation of high precision astrometric instruments the…

Astrophysics · Physics 2009-10-31 Neda Safizadeh , Neal Dalal , Kim Griest