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Related papers: Gravitational Microlensing Near Caustics II: Cusps

200 papers

We use a series of ray-tracing experiments to determine the magnification distribution of high-redshift sources by gravitational lensing. We determine empirically the relation between magnification and redshift, for various cosmological…

Astrophysics · Physics 2009-11-13 Hugo Martel , Premana Premadi

We present PLANET observations of OGLE-1999-BUL-23, a binary-lens microlensing event towards the Galactic bulge. PLANET observations in the I and V bands cover the event from just before the first caustic crossing until the end of the…

When the source in a 4-image gravitational lens lies close to a "fold" caustic, two of the lensed images lie close together. If the lens potential is smooth on the scale of the separation between the two close images, then the difference…

Astrophysics · Physics 2009-11-10 Charles R. Keeton , B. Scott Gaudi , A. O. Petters

Gravitational lensing causes a correlation between a population of foreground large-scale structures and the observed number density of the background distant galaxies as a consequence of the flux magnification and the lensing area…

Astrophysics · Physics 2009-11-06 Takashi Hamana

We simulated both the matter and light (galaxy) distributions in a wedge of the universe and calculated the gravitational lensing magnification caused by the mass along the line of sight of galaxies and galaxy groups identified in sky…

Astrophysics · Physics 2009-11-10 Antonio C. C. Guimarães , Adam D. Myers , Tom Shanks

Galaxy-galaxy or galaxy-quasar lensing can provide important information on the mass distribution in the Universe. It consists of correlating the lensing signal (either shear or magnification) of a background galaxy/quasar sample with the…

Astrophysics · Physics 2009-05-05 R. Ziour , L. Hui

We use a high-resolution $N$-body simulation to investigate the influence of background galaxy properties, including redshift, size, shape and clustering, on the efficiency of forming giant arcs by gravitational lensing of rich galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 G. J. Gao , Y. P. Jing , S. Mao , G. L. Li , X. Kong

Gravitational lensing of a background source by a foreground galaxy lens occasionally produces four images of the source. The cusp and the fold relations impose conditions on the ratios of magnifications of these four-image lenses. In this…

Astrophysics · Physics 2009-11-11 Amir Babak Aazami , Priyamvada Natarajan

The transparent Sun is modeled as a spherically symmetric and centrally condensed gravitational lens using recent Standard Solar Model (SSM) data. The Sun's minimum focal length is computed to a refined accuracy of 23.5 +/- 0.1 AU, just…

Astrophysics · Physics 2011-12-13 Bijunath Patla , Robert J. Nemiroff

Numerical simulations and theoretical studies of the gravitational microlensing effect of a population of small bodies distributed along the line of sight to a compact light source such as a quasar indicate that caustic crossing effects…

Astrophysics · Physics 2007-05-23 M. R. S. Hawkins

The magnifications of the images in a strong gravitational lens system are sensitive to small mass clumps in the lens potential; this effect has been used to infer the amount of substructure in galaxy dark matter halos. I study the theory…

Astrophysics · Physics 2009-11-07 Charles R. Keeton

Gravitational lensing has become one of the most powerful tools available for investigating the 'dark side' of the universe. Cosmological strong gravitational lensing, in particular, probes the properties of the dense cores of dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-30 Nan Li , Michael D. Gladders , Esteban M. Rangel , Michael K. Florian , Lindsey E. Bleem , Katrin Heitmann , Salman Habib , Patricia Fasel

In this letter, we exploit the gravitational potential of the rich cluster A2218 as a magnifying glass. We demonstrate that the magnification due to the cluster allows us to observe distant background galaxies at a comparable level of…

Gravitational lensing deals with general-relativistic effects in the propagation of electromagnetic radiation. We consider wavelength-dependent contributions in case of a (micro)lensing of an extended Gaussian source by a point mass under…

Astrophysics of Galaxies · Physics 2012-11-07 V. I. Zhdanov , D. V. Gorpinchenko

Microlensing is a powerful tool for studying stellar atmospheres because as the source crosses regions of formally infinite magnification (caustics) the surfaceof the star is resolved, thereby allowing one to measure the radial intensity…

Astrophysics · Physics 2009-10-30 B. Scott Gaudi , Andrew Gould

Lensing in the context of rich clusters is normally quantified from small image distortions, yielding a relative mass distribution in the limit of weak lensing. Here we show the magnification effect of lensing can also be mapped over a…

Astrophysics · Physics 2016-08-30 Tom Broadhurst

Lens magnification by galaxy clusters induces characteristic spatial variations in the number counts of background sources, amplifying their observed fluxes and expanding the area of sky, the net effect of which, known as magnification…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Keiichi Umetsu

We propose a method for detecting gravitational magnification of distant sources, like quasars, due to absorber systems detected in their spectra. We first motivate the use of metal absorption lines rather than Lyman-alpha lines, then we…

Astrophysics · Physics 2009-11-10 Brice Ménard

Extended source effects can be seen in gravitational lensing events when sources cross critical lines. Those events probe the stellar intensity profile and could be used to measure limb darkening coefficients to test stellar model…

Instrumentation and Methods for Astrophysics · Physics 2019-08-14 Hans J. Witt , F. Atrio-Barandela

In the gravitational lensing of gravitational waves, the wave optics should be used instead of the geometrical optics when the wavelength $\lambda$ of the gravitational waves is longer than the Schwarzschild radius of the lens mass $M_L$.…

Astrophysics · Physics 2009-11-07 Ryuichi Takahashi , Takashi Nakamura