Concept
Einstein ring
Related publications (88)
The impact of human expert visual inspection on the discovery of strong gravitational lenses
Frédéric Courbin, Benjamin Yvan Alexandre Clement, Martin Raoul Robert Millon, Eric Gérard Guy Paic, Hung-Hsu Chan, Karina Alexandra Rojas Olate, Rémy Elie Joseph, Elodie Marie Charlène Savary, Yue Pan
We investigate the ability of human 'expert' classifiers to identify strong gravitational lens candidates in Dark Energy Survey like imaging. We recruited a total of 55 people that completed more than 25 per cent of the project. During the classification t ...
OXFORD UNIV PRESS2023Probing compact dark matter objects with microlensing in gravitationally lensed quasars
Frédéric Courbin, Martin Raoul Robert Millon, Eric Gérard Guy Paic, Hung-Hsu Chan, Petra Awad
The microlensing signal in the light curves of gravitationally lensed quasars can shed light on the dark matter (DM) composition in their lensing galaxies. Here, we investigate a sample of six lensed quasars from the most recent and best COSMOGRAIL observa ...
EDP SCIENCES S A2023SEAGLE III: Towards resolving the mismatch in the dark-matter fraction in early-type galaxies between simulations and observations
Georgios Vernardos, Matthieu Schaller
The central dark-matter fraction of galaxies is sensitive to feedback processes during galaxy formation. Strong gravitational lensing has been effective in the precise measurement of the dark-matter fraction inside massive early-type galaxies. Here, we com ...
OXFORD UNIV PRESS2022Time-delay estimation in unresolved lensed quasars
Time-delay cosmography can be used to infer the Hubble parameter H-0 by measuring the relative time delays between multiple images of gravitationally lensed quasars. A few of such systems have already been used to measure H-0: Their time delays were determ ...
OXFORD UNIV PRESS2022Teaching machines how to find strongly lensed galaxies in cosmological sky surveys.
Analyzing gravitationally lensed objects enables a wide range of physical and cosmological applications, such as probing the dark matter content in galaxies and clusters or measuring the Universe's expansion rate.The precision of these applications can be ...
EPFL2022Simulating time-varying strong lenses
We present a self-consistent and versatile forward modelling software package that can produce time series and pixel-level simulations of time-varying strongly lensed systems. The time dimension, which needs to take into account different physical mechanis ...
OXFORD UNIV PRESS2022Next generation modeling techniques for strong gravitational lensing and measuring the Hubble constant
For many years, observations of the Universe suggest a series problems with our theoretical models, particularly its dark energy and dark matter components. Fortunately, the Universe also provides us with a tool to solve these problems, called strong gravi ...
EPFL2022Strong lensing in UNIONS: Toward a pipeline from discovery to modeling
Frédéric Courbin, Benjamin Yvan Alexandre Clement, Cameron Alexander Campbell Lemon, Hung-Hsu Chan, Karina Alexandra Rojas Olate, Georgios Vernardos, Elodie Marie Charlène Savary
We present a search for galaxy-scale strong gravitational lenses in the initial 2500 square degrees of the Canada-France Imaging Survey (CFIS). We designed a convolutional neural network (CNN) committee that we applied to a selection of 2 344 002 r-band im ...
EDP SCIENCES S A2022SLITRONOMY: Towards a fully wavelet-based strong lensing inversion technique
Frédéric Courbin, Aymeric Alexandre Galan, Austin Chandler Peel, Rémy Elie Joseph
Strong gravitational lensing provides a wealth of astrophysical information on the baryonic and dark matter content of galaxies. It also serves as a valuable cosmological probe by allowing us to measure the Hubble constant independently of other methods. T ...
EDP SCIENCES S A2021