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Related papers: Numerically studying the degeneracy problem in ext…

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In this paper, we use three different kinds of observational data, including 130 strong gravitational lensing (SGL) systems, type Ia supernovae (SNeIa: Pantheon and Union2.1) and 31 Hubble parameter data points ($H(z)$) from cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-16 Jing-Wang Diao , Yu Pan , Wenxiao Xu

We estimate the sensitivity of lensing observables to the parameters in the lens model (isothermal sphere/Navarro-Frenk-White profile) parameters and to cosmological parameters. We find that the observables are primarily dependent on the…

Astrophysics · Physics 2009-11-06 Takeshi Chiba , Ryuichi Takahashi

We investigate gravitational microlensing signals produced by a spatially extended object transiting in front of a finite-sized source star. The most interesting features arise for lens and source sizes comparable to the Einstein radius of…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-28 Djuna Croon , David McKeen , Nirmal Raj , Zihui Wang

It is known that a relative translational motion between the deflector and the observer affects gravitational lensing. In this paper, a lens equation is obtained to describe such effects on actual lensing observables. Results can be easily…

Astrophysics · Physics 2008-11-26 M. Sereno

Among all galactic microlensing events, those involving a passage of the observed source star over the caustic created by a binary lens are particularly useful in providing information about stellar atmospheres, the dynamics of stellar…

Astrophysics · Physics 2009-11-10 M. Dominik

High-cadence microlensing observations uncovered a population of very short-timescale microlensing events, which are believed to be caused by the population of free-floating planets (FFP) roaming the Milky Way. Unfortunately, the light…

We present a quantitative analysis of the effect of microlensing caused by random motion of individual stars in the galaxy which is lensing a background quasar. We calculate a large number of magnification patterns for positions of the…

Astrophysics · Physics 2016-08-30 Joachim Wambsganss , Tomislav Kundic

The inversion of gravitational lens systems is hindered by the fact that multiple mass distributions are often equally compatible with the observed properties of the images. Besides using clear examples to illustrate the effect of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 J. Liesenborgs , S. De Rijcke

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

(abridged) Using the particularly long gravitational microlensing event OGLE-2014-BLG-1186 with a time-scale $t_\mathrm{E}$ ~ 300 d, we present a methodology for identifying the nature of localised deviations from single-lens point-source…

This paper is the second of a series that investigates the stochasticity and degeneracy problems that hinder the derivation of the age, mass, extinction, and metallicity of unresolved star clusters in external galaxies when broad-band…

Solar and Stellar Astrophysics · Physics 2014-09-10 Philippe de Meulenaer , Donatas Narbutis , Tadas Mineikis , Vladas Vansevičius

We investigate the extended source size effects on gravitational lensing in which a lens consists of a smooth potential and small mass clumps (``substructure lensing''). We first consider a lens model that consists of a clump modeled as a…

Astrophysics · Physics 2009-11-10 Kaiki Taro Inoue , Masashi Chiba

Stellar lightcurves from edge-on double white dwarf systems(DWDs) have periodic lensing/eclipsing signals at times of alignment between two components as seen by the observer. Here, we study the characterization and detection of these…

Solar and Stellar Astrophysics · Physics 2025-01-14 Sedighe Sajadian

Gravitational microlensing events are powerful tools for the study of stellar populations. In particular, they can be used to discover and study a variety of binary systems. A large number of binary lenses have already been found through…

Astrophysics of Galaxies · Physics 2015-09-09 Xinyi Guo , Ann Esin , Rosanne Di Stefano , Jeffrey Taylor

We study a class of degenerate parabolic equations with boundary point degeneracy in dimensions N>=2 and investigate the associated boundary observability problem by means of shape design. While one-dimensional degenerate models have been…

Analysis of PDEs · Mathematics 2026-03-27 Donghui Yang , Jie Zhong

While most strong-gravitational-lensing systems may be roughly modelled by a single massive object between the source and the observer, in the details all the structures near the light path contribute to the observed images. These…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-01 Pierre Fleury , Julien Larena , Jean-Philippe Uzan

We study with semi-analytical methods the statistics of pronounced arcs caused by lensing of galaxies by foreground galaxy clusters. For the number density and redshift distribution of rich clusters we use Press-Schechter theory, normalized…

Astrophysics · Physics 2017-10-04 R. Kaufmann , N. Straumann

Cosmological parameter constraints from observations of time-delay lenses are becoming increasingly precise. However, there may be significant bias and scatter in these measurements due to, among other things, the so-called mass-sheet…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-27 Amitpal S. Tagore , David J. Barnes , Neal Jackson , Scott T. Kay , Matthieu Schaller , Joop Schaye , Tom Theuns

We compute a microlensing map for the Galactic bar. The predicted event rate and event duration distribution are consistent with the $55$ events recently reported by the MACHO and OGLE collaborations. Most of the events are due to lensing…

Astrophysics · Physics 2015-06-24 HongSheng Zhao , R. M. Rich , D. N. Spergel

Context. Strong lenses are a biased subset of the general population of galaxies. Aims. The goal of this work is to quantify how lens galaxies and lensed sources differ from their parent distribution, namely the strong lensing bias.…

Astrophysics of Galaxies · Physics 2023-09-29 Alessandro Sonnenfeld , Shun-Sheng Li , Giulia Despali , Raphael Gavazzi , Anowar J. Shajib , Edward N. Taylor