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Related papers: Gravitational lens surveys with LOFAR

200 papers

Strong gravitational lenses provide unique laboratories for cosmological and astrophysical investigations, but they must first be discovered - a task that can be met with significant contamination by other astrophysical objects and…

Strong gravitational lenses allow us to peer into the farthest reaches of space by bending the light from a background object around a massive object in the foreground. Unfortunately, these lenses are extremely rare, and manually finding…

Instrumentation and Methods for Astrophysics · Physics 2022-10-24 Stephen Sheng , Keerthi Vasan G. C , Chi Po Choi , James Sharpnack , Tucker Jones

Recent developments in gravitational lensing astronomy have paved the way to genuine mappings of the gravitational potential at cosmological scales. We stress that comparing these data with traditional large scale structure surveys will…

High Energy Physics - Phenomenology · Physics 2009-10-31 Jean-Philippe Uzan , Francis Bernardeau

The 2 degree Field (2dF) galaxy redshift survey will involve obtaining approximately 2.5 x 10^5 spectra of objects previously identified as galaxy candidates on morphological grounds. Included in these spectra should be about ten…

Astrophysics · Physics 2009-11-06 Daniel J. Mortlock , Darren S. Madgwick , Ofer Lahav

The Faraday rotation measurements of multiply-imaged gravitational lens systems can be effectively used to probe the existence of large-scale ordered magnetic fields in lensing galaxies and galaxy clusters. The available sample of lens…

Astrophysics · Physics 2009-06-25 D. Narasimha , S. M. Chitre

In this work, we present our classification algorithm to identify strong gravitational lenses from wide-area surveys using machine learning convolutional neural network; LensExtractor. We train and test the algorithm using a wide variety of…

Instrumentation and Methods for Astrophysics · Physics 2018-04-11 Milad Pourrahmani , Hooshang Nayyeri , Asantha Cooray

I review the observations of gravitationally lensed quasars. These systems are important because they allow us to probe the properties of the lensing galaxies at various scales, and they also allow insights into the structures of the…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-16 Neal Jackson

Gravitational lensing is a powerful astrophysical and cosmological probe and is particularly valuable at submillimeter wavelengths for the study of the statistical and individual properties of dusty starforming galaxies. However the…

We perform a semi-automated search for strong gravitational lensing systems in the 9,000 deg$^2$ Dark Energy Camera Legacy Survey (DECaLS), part of the DESI Legacy Imaging Surveys (Dey et al.). The combination of the depth and breadth of…

We consider the possibility that future wide-field time-domain optical imaging surveys may be able to discover gravitationally lensed quasar pairs through serendipitous measurements of their time delays. We discuss the merits such a…

Astrophysics · Physics 2009-11-10 Bart Pindor

Most surveys for multiply-imaged gravitational lenses, outside of rich galaxy clusters, are based on sifting through large samples of distant sources to identify the rare examples of lensing. An alternative strategy, based on the selection…

Searches and analyses of strong gravitational lenses are challenging due to the rarity and image complexity of these astronomical objects. Next-generation surveys (both ground- and space-based) will provide more opportunities to derive…

Astrophysics of Galaxies · Physics 2019-11-18 Clecio Bom , Jason Poh , Brian Nord , Manuel Blanco-Valentin , Luciana Dias

A complete manual search has been carried out of the list of 285423 objects, nearly all of them galaxies, identified in the COSMOS field that are brighter than I=25. Two certain and one highly probable new gravitational lenses are found, in…

Astrophysics · Physics 2009-11-13 Neal Jackson

Along their path from source to observer, gravitational waves may be gravitationally lensed by massive objects. This results in distortions of the observed signal which can be used to extract new information about fundamental physics,…

We present a novel machine learning based approach for detecting galaxy-scale gravitational lenses from interferometric data, specifically those taken with the International LOFAR Telescope (ILT), which is observing the northern radio sky…

Astrophysics of Galaxies · Physics 2022-08-03 S. Rezaei , J. P. McKean , M. Biehl , W. de Roo1 , A. Lafontaine

We have conducted a search for new strong gravitational lensing systems in the Dark Energy Spectroscopic Instrument Legacy Imaging Surveys' Data Release 8. We use deep residual neural networks, building on previous work presented in Huang…

Instrumentation and Methods for Astrophysics · Physics 2021-03-10 X. Huang , C. Storfer , A. Gu , V. Ravi , A. Pilon , W. Sheu , R. Venguswamy , S. Banka , A. Dey , M. Landriau , D. Lang , A. Meisner , J. Moustakas , A. D. Myers , R. Sajith , E. F. Schlafly , D. J. Schlegel

Strong gravitational lensing of quasars has the potential to unlock the poorly understood physics of these fascinating objects, as well as serve as a probe of the lensing mass distribution and of cosmological parameters. In particular,…

Astrophysics of Galaxies · Physics 2023-12-05 G. Vernardos , D. Sluse , D. Pooley , R. W. Schmidt , M. Millon , L. Weisenbach , V. Motta , T. Anguita , P. Saha , M. O'Dowd , A. Peel , P. L. Schechter

We present a pipeline to identify photometric variability within strong gravitationally lensing candidates, in the DESI Legacy Imaging Surveys. In our first paper (Sheu et al. 2023), we laid out our pipeline and presented seven new…

Strong gravitationally lensed quasars provide powerful means to study galaxy evolution and cosmology. Current and upcoming imaging surveys will contain thousands of new lensed quasars, augmenting the existing sample by at least two orders…

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