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Strong gravitational lensing by galaxies is a powerful tool for studying cosmology and galaxy structure. The China Space Station Telescope (CSST) will revolutionize this field by discovering up to $\sim$100,000 galaxy-scale strong lenses, a…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-12 Hengyu Wu , Yun Chen , Tonghua Liu , Xiaoyue Cao , Tian Li , Hui Li , Nan Li , Ran Li , Tengpeng Xu

We present a new non-parametric method for determining mean 3D density and mass profiles from weak lensing measurements around stacked samples of galaxies or clusters, that is, from measurement of the galaxy-shear or cluster-shear…

In the upcoming synoptic all--sky survey era of astronomy, thousands of new multiply imaged quasars are expected to be discovered and monitored regularly. Light curves from the images of gravitationally lensed quasars are further affected…

Instrumentation and Methods for Astrophysics · Physics 2015-06-24 Georgios Vernardos , Christopher J. Fluke , Nicholas F. Bate , Darren Croton , Dany Vohl

When gravitational waves pass near massive astrophysical objects, they can be gravitationally lensed. The lensing can split them into multiple wave-fronts, magnify them, or imprint beating patterns on the waves. Here we focus on the…

High Energy Astrophysical Phenomena · Physics 2021-11-17 A. Renske A. C. Wierda , Ewoud Wempe , Otto A. Hannuksela , Léon V. E. Koopmans , Chris Van Den Broeck

Observations of quasars (QSOs) shining through or close to galaxies offer a way to probe the properties of the foreground matter through dust extinction and gravitational lensing. In this paper the feasibility of measuring the dust…

Astrophysics · Physics 2015-06-24 L. Ostman , A. Goobar , E. Mortsell

We report the discovery of a new gravitationally lensed QSO, at a redshift z = 1.689, with four QSO components in a cross-shaped arrangement around a bright galaxy. The maximum separation between images is 2.6 arcsec, enabling a reliable…

Gravitationally lensed supernovae (glSNe) are a powerful tool for exploring the realms of astronomy and cosmology. Time-delay measurements and lens modeling of glSNe can provide a robust and independent method for constraining the expansion…

High Energy Astrophysical Phenomena · Physics 2025-06-25 Elahe Khalouei , Arman Shafieloo , Alex G. Kim , Ryan E. Keeley , William Sheu , Gregory S. H. Paek , Myungshin Im , Xiaosheng Huang , Hyung Mok Lee

We present a systematic search for wide-separation (Einstein radius >1.5"), galaxy-scale strong lenses in the 30 000 sq.deg of the Pan-STARRS 3pi survey on the Northern sky. With long time delays of a few days to weeks, such systems are…

Astrophysics of Galaxies · Physics 2021-04-08 R. Canameras , S. Schuldt , S. H. Suyu , S. Taubenberger , T. Meinhardt , L. Leal-Taixe , C. Lemon , K. Rojas , E. Savary

SDSS J2222+2745 is a galaxy cluster at z=0.49, strongly lensing a quasar at z=2.805 into six widely separated images. In recent HST imaging of the field, we identify additional multiply lensed galaxies, and confirm the sixth quasar image…

Strongly lensed supernovae (glSNe) provide a powerful, independent method to measure the Hubble constant, $H_{0}$, through time delays between their multiple images. The accuracy of this measurement depends critically on both the precision…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-05 Yushan Xie , Huanyuan Shan , Yiping Shu , Nan Li , Ji Yao , Ran Li , Xiaoyue Cao , Zizhao He , Yin Li , Eric Jullo , Jean-Paul Kneib , Guoliang Li

Time-domain surveys have advanced astronomical research by revealing diverse variable phenomena, from stellar flares to transient events. The scale and complexity of survey data, along with the demand for rapid classification, present…

Instrumentation and Methods for Astrophysics · Physics 2025-12-10 Xiaoxiong Zuo , Yihan Tao , Yang Huang , Zhixuan Kang , Huaxi Chen , Chenzhou Cui , Jiashu Pan , Xiao Kong , Xiaoyu Tang , Henggeng Han , Haiyang Mu , Yunfei Xu , Dongwei Fan , Guirong Xue , Ali Luo , Jifeng Liu

We report the discovery, spectroscopic confirmation, and mass modelling of the gravitationally lensed quasar system PS J0630-1201. The lens was discovered by matching a photometric quasar catalogue compiled from Pan-STARRS and WISE…

Identifying and handling label errors can significantly enhance the accuracy of supervised machine learning models. Recent approaches for identifying label errors demonstrate that a low self-confidence of models with respect to a certain…

Machine Learning · Computer Science 2024-05-17 Johannes Jakubik , Michael Vössing , Manil Maskey , Christopher Wölfle , Gerhard Satzger

We present a tool to generate mock quasar microlensing light curves and sample them according to any observing strategy. An updated treatment of the fixed and random velocity components of observer, lens, and source is used, together with a…

Astrophysics of Galaxies · Physics 2020-11-02 Favio Neira , Timo Anguita , Georgios Vernardos

An ESO Key programme dedicated to an Homogeneous Bright QSO Survey (HBQS) has been completed. 327 QSOs (Mb<-23, 0.3<z<2.2) have been selected over 555 deg^2 with 15<B<18.75. For B<16.4 the QSO surface density turns out to be a factor 2.2…

Astrophysics · Physics 2009-10-28 Fabio La Franca , Stefano Cristiani

The goal of this work is to obtain a Hubble constant estimate through the study of the quadruply lensed, variable QSO SDSSJ1433+6007. To achieve this we combine multi-filter, archival $\textit{HST}$ data for lens modelling and a dedicated…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-28 G. Queirolo , S. Seitz , A. Riffeser , M. Kluge , R. Bender , C. Gössl , U. Hopp , C. Ries , M. Schmidt , R. Zöller

We introduce a novel method for weak-lensing measurements, which is based on a mathematically exact deconvolution of the moments of the apparent brightness distribution of galaxies from the telescope's PSF. No assumptions on the shape of…

Instrumentation and Methods for Astrophysics · Physics 2012-04-24 Peter Melchior , Massimo Viola , Björn Malte Schäfer , Matthias Bartelmann

Lane detection is a fundamental task in autonomous driving. While the problem is typically formulated as the detection of continuous boundaries, we study the problem of detecting lane boundaries that are sparsely marked by 2D points with…

Robotics · Computer Science 2024-05-28 Ivo Ivanov , Carsten Markgraf

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

Cosmological galaxy surveys aim at mapping the largest volumes to test models with techniques such as cluster abundance, cosmic shear correlations or baryon acoustic oscillations (BAO), which are designed to be independent of galaxy bias.…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 E. Gaztanaga , M. Eriksen , M. Crocce , F. Castander , P. Fosalba , P. Marti , R. Miquel , A. Cabre