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Related papers: Data Mining for Gravitationally Lensed Quasars

200 papers

We describe Space Warps, a novel gravitational lens discovery service that yields samples of high purity and completeness through crowd-sourced visual inspection. Carefully produced colour composite images are displayed to volunteers via a…

The Hubble tension, revealed by a $\sim 5\sigma$ discrepancy between measurements of the Hubble-Lemaitre constant from early- and local-Universe observations, is one of the most significant problems in modern cosmology. In order to better…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-12 Zizhao He , Nan Li , Xiaoyue Cao , Rui Li , Hu Zou , Simon Dye

We discuss whether modern machine learning methods can be used to characterize the physical nature of the large number of objects sampled by the modern multi-band digital surveys. In particular, we applied the MLPQNA (Multi Layer Perceptron…

Astrophysics of Galaxies · Physics 2015-06-17 Massimo Brescia , Stefano Cavuoti , Giuseppe Longo

We report new high-quality galaxy scale strong lens candidates found in the Kilo Degree Survey data release 4 using Machine Learning. We have developed a new Convolutional Neural Network (CNN) classifier to search for gravitational arcs,…

Weak gravitational lensing is one of the most promising cosmological probes of the late universe. Several large ongoing (DES, KiDS, HSC) and planned (LSST, EUCLID, WFIRST) astronomical surveys attempt to collect even deeper and larger scale…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-06 Dezső Ribli , Bálint Ármin Pataki , José Manuel Zorrilla Matilla , Daniel Hsu , Zoltán Haiman , István Csabai

The statistics of gravitationally lensed quasars with multiple images in the 0.1''-7'' range have been measured in various surveys. Little is known, however, about lensed-quasar statistics at larger image separations, which probe masses on…

Astrophysics · Physics 2009-10-28 Dan Maoz , Hans-Walter Rix , Avishay Gal-Yam , Andrew Gould

Searches for continuous gravitational waves target nearly monochromatic gravitational wave emission from e.g. non-axysmmetric fast-spinning neutron stars. Broad surveys often require to explicitly search for a very large number of different…

General Relativity and Quantum Cosmology · Physics 2022-12-14 Benjamin Steltner , Thorben Menne , Maria Alessandra Papa , Heinz-Bernd Eggenstein

We report the discovery of a new gravitationally lensed quasar (double) from the Optical Gravitational Lensing Experiment (OGLE) identified inside the $\sim$670 sq. deg area encompassing the Magellanic Clouds. The source was selected as one…

We apply the iterative MCS deconvolution method (ISMCS) to near-IR HST archives data of seven gravitationally lensed quasars currently monitored by the COSMOGRAIL collaboration: HE 0047-1756, RX J1131-1231, SDSS J1138+0314, SDSS J1155+6346,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Virginie Chantry , Dominique Sluse , Pierre Magain

We present the first results of our dedicated programme of automatised classification of galaxies, stars and quasars in the mid-infrared all-sky data from the WISE survey. We employ the Support Vector Machines (SVM) algorithm, which defines…

Astrophysics of Galaxies · Physics 2015-12-14 Agnieszka Kurcz , Magdalena Krupa , Maciej Bilicki , Aleksandra Solarz , Agnieszka Pollo , Katarzyna Małek

Strong gravitational lensing of gravitational waves (GWs) occurs when the GWs from a compact binary system travel near a massive object. The mismatch between a lensed signal and unlensed templates determines whether lensing can be…

General Relativity and Quantum Cosmology · Physics 2023-05-24 Saif Ali , Evangelos Stoikos , Evan Meade , Michael Kesden , Lindsay King

The sensitivity and wide area reached by ongoing and future wide-field optical surveys allows for the detection of an increasing number of galaxy clusters uniquely through their weak lensing (WL) signal. This motivates the development of…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-18 G. Leroy , S. Pires , G. W. Pratt , C. Giocoli

We perform a search for galaxy-galaxy strong lens systems using a convolutional neural network (CNN) applied to imaging data from the first public data release of the DECam Local Volume Exploration Survey (DELVE), which contains $\sim 520$…

We present a classification-based approach to identify quasi-stellar radio sources (quasars) in the Sloan Digital Sky Survey and evaluate its performance on a manually labeled training set. While reasonable results can already be obtained…

Instrumentation and Methods for Astrophysics · Physics 2016-11-18 Fabian Gieseke , Kai Lars Polsterer , Andreas Thom , Peter-Christian Zinn , Dominik Bomanns , Ralf-Jürgen Dettmar , Oliver Kramer , Jan Vahrenhold

Gravitational lensing by compact, small-scale intervening masses causes frequency-dependent distortions to gravitational-wave events. The optimal signal-to-noise ratio (SNR) is often used as a proxy for the detectability of exotic signals…

General Relativity and Quantum Cosmology · Physics 2025-04-14 Juno C. L. Chan , Eungwang Seo , Alvin K. Y. Li , Heather Fong , Jose M. Ezquiaga

We report the discoveries of the two-image gravitationally lensed quasars, SDSS J0746+4403 and SDSS J1406+6126, selected from the Sloan Digital Sky Survey (SDSS). SDSS J0746+4403, which will be included in our lens sample for statistics and…

Machine learning can provide powerful tools to detect patterns in multi-dimensional parameter space. We use K-means -a simple yet powerful unsupervised clustering algorithm which picks out structure in unlabeled data- to study a sample of…

Astrophysics of Galaxies · Physics 2016-03-11 Aycha Tammour , Sarah C. Gallagher , Mark Daley , Gordon T. Richards

It is possible to detect gravitationally-lensed quasars spectroscopically if the spectra obtained during galaxy surveys are searched for the presence of quasar emission lines. The up-coming 6 degree Field (6dF) redshift survey on the United…

Astrophysics · Physics 2009-11-06 Daniel J. Mortlock , Michael J. Drinkwater

(abridged) Gravitationally lensed quasars can be used as powerful cosmological and astrophysical probes. We can (i) infer the Hubble constant based on the time-delay technique, (ii) unveil substructures along the l.o.s. toward distant…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-05 D. Sluse , V. Chantry , P. Magain , F. Courbin , G. Meylan

We report on i-band snapshot observations of 157 Sloan Digital Sky Survey (SDSS) quasars at 4<z<5.4 using the Advanced Camera for Surveys on the Hubble Space Telescope (HST) to search for evidence of gravitational lensing of these sources.…