Publications de Frédéric Courbin

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GRavitational lEnsing Accuracy Testing 2010 (GREAT10) is a public image analysis challenge aimed at the development of algorithms to analyze astronomical images. Specifically, the challenge is to measure varying image distortions in the presence of a varia ...

We report the discovery of a complete Einstein ring around the elliptical galaxy NGC 6505, at z = 0.042. This is the first strong gravitational lens discovered in Euclid and the first in an NGC object from any survey. The combination of the low redshift of ...

We provide an early assessment of the imaging capabilities of the Euclid space mission to deeply probe nearby star-forming regions and associated very young open clusters, and in particular, to determine to which extent it can shed light into the newborn f ...

Measuring time delays between the multiple images of gravitationally lensed quasars is now recognized as a competitive way to constrain the cosmological parameters, and it is complementary with other cosmological probes. This requires long and well sampled ...

The Euclid mission - with its spectroscopic galaxy survey covering a sky area over 15 000 deg(2) in the redshift range 0.9 < z < 1.8 - will provide a sample of tens of thousands of cosmic voids. This paper thoroughly explores for the first time the constra ...

We present the results of a new search for galaxy-scale strong lensing systems in CFHTLS Wide. Our lens-finding technique involves a preselection of potential lens galaxies, applying simple cuts in size and magnitude. We then perform a Principal Component ...

The Euclid mission of the European Space Agency will provide weak gravitational lensing and galaxy clustering surveys that can be used to constrain the standard cosmological model and its extensions, with an opportunity to test the properties of dark matte ...

Galaxy-scale gravitational lenses are often modeled with two-component mass profiles where one component represents the stellar mass and the second is a Navarro Frenk White (NFW) profile representing the dark matter. Outside of the spherical case, the NFW ...

Sky survey telescopes and powerful targeted telescopes play complementary roles in astronomy. In order to investigate the nature and characteristics of the motions of very faint objects, a flexibly-pointed instrument capable of high astrometric accuracy is ...

The instruments at the focus of the Euclid space observatory offer superb, diffraction-limited imaging over an unprecedented (from space) wide field of view of 0.57 deg2. This exquisite image quality has the potential to produce high-precision astrometry f ...

Flux ratio anomalies in strong gravitationally lensed quasars constitute a unique way to probe the abundance of non-luminous dark matter haloes, and hence the nature of dark matter. In this paper, we identify double-imaged quasars as a statistically effici ...

We present starred, a point-spread function (PSF) reconstruction, two-channel deconvolution, and light-curve extraction method designed for high-precision photometric measurements in imaging time series. An improved resolution of the data is targeted rathe ...

To constrain cosmological models beyond ACDM, the development of the Euclid analysis pipeline requires simulations that capture the non-linear phenomenology of such models. We present an overview of numerical methods and N-body simulation codes developed t ...

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 ...

Aims. We validate a semi-analytical model for the covariance of the real-space two-point correlation function of galaxy clusters. Methods. Using 1000 PINOCCHIO light cones mimicking the expected Euclid sample of galaxy clusters, we calibrated a simple mode ...

As part of the Euclid Early Release Observations (ERO) programme, we analysed deep, wide-field imaging from the VIS and NISP instruments of two Milky Way globular clusters (GCs), namely NGC 6254 (M10) and NGC 6397, to look for observational evidence of the ...

We conducted an exploratory search for quasars at z similar to 6-8, using the Early Data Release (EDR) from the United Kingdom Infrared Deep Sky Survey (UKIDSS) cross-matched to panoramic optical imagery. High-redshift quasar candidates are chosen using mu ...

The anomalous flux ratios between quasar images are suspected of being caused by substructures in lens galaxies. We present new deep and high-resolution H and Ks imaging of the strongly lensed quasar SDSS J0924+0219 obtained using the ESO VLT with adaptive ...

Future deep HI surveys will be essential for understanding the nature of galaxies and the content of the Universe. However, the large volume of these data will require distributed and automated processing techniques. We introduce LiSA, a set of python modu ...

When an image of a strongly lensed quasar is microlensed, the different components of its spectrum are expected to be differentially magnified owing to the different sizes of the corresponding emitting region. Chromatic changes are expected to be observed ...

Frédéric Courbin

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Gravitational Lensing Accuracy Testing 2010 (Great10) Challenge Handbook

Euclid: A complete Einstein ring in NGC 6505

Euclid: Early Release Observations - A glance at free-floating newborn planets in the σ Orionis cluster

COSMOGRAIL: the COSmological MOnitoring of GRAvItational Lenses XI. Techniques for time delay measurement in presence of microlensing

Euclid: Cosmological forecasts from the void size function

The PCA Lens-Finder: application to CFHTLS

Euclid preparation: LVI. Sensitivity to non-standard particle dark matter models

The ellipticity parameterization for an NFW profile: An overlooked angular structure in strong lens modeling

Faint objects in motion: the new frontier of high precision astrometry

Euclid: High-precision imaging astrometry and photometry from Early Release Observations I. Internal kinematics of NGC 6397 by combining Euclid and Gaia data

Exploiting flux ratio anomalies to probe warm dark matter in future large-scale surveys

Image Deconvolution and Point-spread Function Reconstruction with STARRED: A Wavelet-based Two-channel Method Optimized for Light-curve Extraction

Euclid preparation: LXII. Simulations and non-linearities beyond Lambda cold dark matter. 1. Numerical methods and validation

The impact of human expert visual inspection on the discovery of strong gravitational lenses

Euclid preparation: XXXV. Covariance model validation for the two-point correlation function of galaxy clusters

Euclid: Early Release Observations – Unveiling the morphology of two Milky Way globular clusters out to their periphery

An exploratory search for z greater than or similar to 6 quasars in the ukidss early data release

VLT adaptive optics search for luminous substructures in the lens galaxy towards SDSS J0924+0219

Lightweight HI source finding for next generation radio surveys

Microlensing of the broad line region in 17 lensed quasars