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The numerical kernel approach to difference imaging has been implemented and applied to gravitational microlensing events observed by the PLANET collaboration. The effect of an error in the source-star coordinates is explored and a new…

Although many exoplanets have been indirectly detected over the last years, direct imaging of them with ground-based telescopes remains challenging. In the presence of atmospheric fluctuations, it is ambitious to resolve the high brightness…

Instrumentation and Methods for Astrophysics · Physics 2023-02-08 Jakob Roth , Gianluca Li Causi , Vincenzo Testa , Philipp Arras , Torsten A. Enßlin

We outline a simple procedure designed for \emph{automatically} finding sets of multiple images in strong lensing (SL) clusters. We show that by combining (a) an arc-finding (or source extracting) program, (b) photometric redshift…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-08 Mauricio Carrasco , Adi Zitrin , Gregor Seidel

It is plausible that most of the Stars in the Milky Way (MW) Galaxy, like the Sun, consist of planetary systems, instead of a single planet. Out of the estimately discovered 3,950 planet-hosting stars, about 860 of them are known to be…

Earth and Planetary Astrophysics · Physics 2023-05-31 Hossein Fatheddin , Sedighe Sajadian

The goal of this paper is to develop a machine learning model to analyze the main gravitational lens and detect dark substructure (subhalos) within simulated images of strongly lensed galaxies. Using the technique of image segmentation, we…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-27 Bryan Ostdiek , Ana Diaz Rivero , Cora Dvorkin

We present a new method designed for optimal subtraction of two images with different seeing. Using image subtraction appears to be essential for the full analysis of the microlensing survey images, however a perfect subtraction of two…

Astrophysics · Physics 2016-08-30 C. Alard , R. H. Lupton

We analyze photometric observations of stars, which experienced microlensing events at the considered time, in order to compare the efficiency of detecting exoplanets in observations performed at thirteen different telescopes and with…

Earth and Planetary Astrophysics · Physics 2025-09-24 S. I. Ipatov

We present a new algorithm to search for distant clusters of galaxies on catalogues deriving from imaging data, as those of the ESO Imaging Survey. Our algorithm is a matched filter one, similar to that adopted by Postman et al. (1996),…

Astrophysics · Physics 2007-05-23 C. Lobo , A. Iovino , D. Lazzati , G. Chincarini

High-contrast imaging for the detection and characterization of exoplanets relies on the instrument's capability to block out the light of the host star. Some current post-processing methods for calibrating out the residual speckles use…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 Marie Ygouf , Laurent M. Mugnier , David Mouillet , Thierry Fusco , Jean-Luc Beuzit

The microlensing effect has developed into a powerful technique for a diverse range of applications including exoplanet discoveries, structure of the Milky Way, constraints on MAssive Compact Halo Objects, and measurements of the size and…

Astrophysics of Galaxies · Physics 2021-12-22 Xuechun Chen , Yiping Shu , Guoliang Li , Wenwen Zheng

The gravitational microlensing method of discovering exoplanets and multi-star systems can produce degenerate solutions, some of which require in-depth analysis to uncover. We propose a new parameter space that can be used to sample…

Earth and Planetary Astrophysics · Physics 2024-09-16 Kylie E. Hall , Jennifer C. Yee , In-Gu Shin , Hongjing Yang , Jiyuan Zhang

The detection of exoplanets in coronographic images is severely limited by residual starlight speckles. Dedicated post-processing can drastically reduce this "stellar leakage" and thereby increase the faintness of detectable exoplanets.…

Instrumentation and Methods for Astrophysics · Physics 2017-11-08 Nicholas Devaney , Éric Thiébaut

An LSST-like survey of the Galactic plane (deep images every 3-4 days) could probe the Galactic distribution of planets by two distinct methods: gravitational microlensing of planets beyond the snow line and transits by planets very close…

Astrophysics of Galaxies · Physics 2013-04-15 Andrew Gould

This paper is devoted to exploring how we can discover and study nearby (< 1-2 kpc) planetary and binary systems by observing their action as gravitational lenses. Lensing can extend the realm of nearby binaries and planets that can be…

Astrophysics · Physics 2008-01-11 R. Di Stefano

We present a new galaxy cluster lens modeling approach, hybrid-Lenstool, that is implemented in the publicly available modeling software Lenstool. hybrid-Lenstool combines a parametric approach to model the core of the cluster, and a…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-26 Anna Niemiec , Mathilde Jauzac , Eric Jullo , Marceau Limousin , Keren Sharon , Jean-Paul Kneib , Priyamvada Natarajan , Johan Richard

Radial velocity surveys for extra-solar planets generally require substantial amounts of large telescope time in order to monitor a sufficient number of stars. Two of the aspects which can limit such surveys are the single-object…

Astrophysics · Physics 2008-11-26 Stephen R. Kane , Donald P. Schneider , Jian Ge

We study the wave optics features of gravitational microlensing by a binary lens composed of a planet and a parent star. In this system, the source star near the caustic line produces a pair of images in which they can play the role of…

Earth and Planetary Astrophysics · Physics 2015-06-05 Ahmad Mehrabi , Sohrab Rahvar

This work proposes a variable neighbourhood search (FTS) that uses a fractal-based local search primarily designed for images. Searching for specific content in images is posed as an optimisation problem, where evidence elements are…

Image and Video Processing · Electrical Eng. & Systems 2026-05-22 Erick O. Rodrigues , Panos Liatsis , Luiz Satoru , Aura Conci

We introduce a deep machine learning approach to studying quasar microlensing light curves for the first time by analyzing hundreds of thousands of simulated light curves with respect to the accretion disc size and temperature profile. Our…

Instrumentation and Methods for Astrophysics · Physics 2019-04-24 Georgios Vernardos , Grigorios Tsagkatakis

We present a new method of discovering galaxy-scale, strongly-lensed QSO systems from unresolved light curves using the autocorrelation function. The method is tested on five rungs of simulated light curves from the Time Delay Challenge 1…

Instrumentation and Methods for Astrophysics · Physics 2021-03-10 Yiping Shu , Vasily Belokurov , N. Wyn Evans