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Related papers: Microlensing near macro-caustics

200 papers

Results from gravitational microlensing suggested the existence of a large population of free-floating planetary mass objects. The main conclusion from this work was partly based on constraints from a direct imaging survey. This survey…

Astrophysics of Galaxies · Physics 2015-06-04 Sascha P. Quanz , David Lafreniere , Michael R. Meyer , Maddalena M. Reggiani , Esther Buenzli

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

Highly magnified stars ($\mu$ $>$ 100) are now outinely identified as transient events at cosmological distances thanks to microlensing by intra-cluster stars near the critical curves of galaxy clusters. Using the {\it James Webb} Space…

We investigate the microlensing effects on a source star surrounded by a circumstellar disk, as a function of wavelength. The microlensing light curve of the system encodes the geometry and surface brightness profile of the disk. In the…

Astrophysics · Physics 2009-11-13 Zheng Zheng , Brice Ménard

Caustic-crossing stars observed in giant arcs behind galaxy clusters provide a powerful probe of dark matter substructure. While previous work has focused on point-like lenses such as primordial black holes, we extend this framework to…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-23 Djuna Croon , Benedict Crossey , Jose Maria Diego , Bradley J. Kavanagh , Jose Maria Palencia

We examine a caustic-straddling arc at $z=0.9397$ in the field of the galaxy cluster MACS J0416.1-2403 ($z=0.397$) using archival multiband HST images and show that its surface brightness exhibits anomalies that can be explained by a single…

Astrophysics of Galaxies · Physics 2019-07-31 Alexander A. Kaurov , Liang Dai , Tejaswi Venumadhav , Jordi Miralda-Escudé , Brenda Frye

Gravitational lensing by a stellar microlens of mass $M$ forms two images separated by micro-arcseconds on the sky and has a time delay of $2\times10^{-5}(M/{\rm M_\odot})$ seconds. Although we cannot resolve such micro-images in the sky,…

Astrophysics of Galaxies · Physics 2025-12-08 Ashish Kumar Meena , Prasenjit Saha

Highly magnified stars residing in caustic crossing lensed galaxies at z ~ 0.7-1.5 in galaxy cluster lensing fields inevitably exhibit recurrent brightening events as they traverse a micro caustic network cast down by foreground…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-14 Xu Han , Liang Dai

Bright sub-mm galaxies are expected to arise in massive highly-biased haloes, and hence exhibit strong clustering. We argue that a valuable tool for measuring these clustering properties is the cross-correlation of sub-mm galaxies with…

Astrophysics · Physics 2009-11-11 Chris Blake , Alexandra Pope , Douglas Scott , Bahram Mobasher

When gravitational waves pass through the nuclear star clusters of galactic lenses, they may be microlensed by the stars. Such microlensing can cause potentially observable beating patterns on the waveform due to waveform superposition and…

High Energy Astrophysical Phenomena · Physics 2021-03-10 Mark H. Y. Cheung , Joseph Gais , Otto A. Hannuksela , Tjonnie G. F. Li

Gravitational microlensing is a powerful method for detecting and characterizing free-floating planetary-mass objects (FFPs). FFPs could have exomoons rotating them. In this work, we study the probability of realizing these systems (i.e.,…

Earth and Planetary Astrophysics · Physics 2023-02-22 Sedighe Sajadian , Parisa Sangtarash

Paczy\'nski (1986) suggested that ``dark" objects in the halo of our Galaxy could enhance the luminosity of foreground stars, acting as gravitational microlenses. Such events has been recently reported by different collaborations. We assume…

Astrophysics · Physics 2007-05-23 Sergio Campana

We propose a direct method to detect close-in giant planets orbiting stars in the Galactic bulge. This method uses caustic-crossing binary microlensing events discovered by survey teams monitoring the bulge to measure light from a planet…

Astrophysics · Physics 2009-10-31 David S. Graff , B. Scott Gaudi

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

Gravitational microlensing of planetary-mass objects (or "nanolensing", as it has been termed) can be used to probe the distribution of mass in a galaxy that is acting as a gravitational lens. Microlensing and nanolensing light curve…

Astrophysics of Galaxies · Physics 2015-06-03 H. Garsden , N. F. Bate , G. F. Lewis

Extended dark matter (DM) substructures may play the role of microlenses in the Milky Way and in extragalactic gravitational lens systems (GLSs). We compare microlensing effects caused by point masses (Schwarzschild lenses) and extended…

Astrophysics of Galaxies · Physics 2022-09-07 E. Fedorova , V. M. Sliusar , V. I. Zhdanov , A. N. Alexandrov , A. Del Popolo , J. Surdej

There are lines of evidence suggesting that some of the observed microlensing events in the direction of the Large Magellanic Cloud (LMC) are caused by ordinary star lenses as opposed to dark Machos in the Galactic halo. Efficient lensing…

Astrophysics · Physics 2009-10-31 HongSheng Zhao , David Graff , Puragra Guhathakurta

If cluster dark matter is in the form of compact objects it will introduce fluctuations into the light curves of distant sources. Current searches for MACHOs in clusters of galaxies focus on monitoring quasars behind nearby systems. This…

Astrophysics · Physics 2009-10-31 Geraint F. Lewis , Rodrigo A. Ibata , J. Stuart B. Wyithe

The spatial distribution of compact dark matter in our Galaxy can be determined in a few years of monitoring Galactic globular clusters for microlensing. Globular clusters are the only dense fields of stars distributed throughout the…

Astrophysics · Physics 2009-10-30 James E. Rhoads , Sangeeta Malhotra

The microlensing signal in the light curves of gravitationally lensed quasars can shed light on the dark matter (DM) composition in their lensing galaxies. Here, we investigate a sample of six lensed quasars from the most recent and best…

Astrophysics of Galaxies · Physics 2023-04-05 Petra Awad , James H. H. Chan , Martin Millon , Frederic Courbin , Eric Paic