Publications de Frédéric Courbin

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Primordial features, in particular oscillatory signals, imprinted in the primordial power spectrum of density perturbations represent a clear window of opportunity for detecting new physics at high-energy scales. Future spectroscopic and photometric measur ...

We present a blind time-delay strong lensing (TDSL) cosmographic analysis of the doubly imaged quasar SDSS 1206+4332. We combine the relative time delay between the quasar images, Hubble Space Telescope imaging, the Keck stellar velocity dispersion of the ...

The Euclid Early Release Observations (ERO) programme targeted the Perseus cluster of galaxies, gathering deep data in the central region of the cluster over 0.7 deg2, including the cluster core up to 0.25 r200. The dataset reaches a point-source depth of ...

We present an algorithm using principal component analysis (PCA) to subtract galaxies from imaging data and also two algorithms to find strong, galaxy-scale gravitational lenses in the resulting residual image. The combined method is optimised to find full ...

We study the constraint on f(R) gravity that can be obtained by photometric primary probes of the Euclid mission. Our focus is the dependence of the constraint on the theoretical modelling of the nonlinear matter power spectrum. In the Hu–Sawicki f(R) grav ...

Context. ALMA observations show that dusty, distant, massive ( M similar to & 1011 M fi) galaxies usually have a remarkable star-formation activity, contributing of the order of 25% of the cosmic star-formation rate density at z similar to 3-5, and up to 3 ...

In recent years, breakthroughs in methods and data have enabled gravitational time delays to emerge as a very powerful tool to measure the Hubble constant H-0. However, published state-of-the-art analyses require of order 1 yr of expert investigator time a ...

We present a blind time-delay cosmographic analysis for the lens system DES J0408-5354. This system is extraordinary for the presence of two sets of multiple images at different redshifts, which provide the opportunity to obtain more information at the cos ...

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 ...

The H0LiCOWcollaboration inferred via strong gravitational lensing time delays a Hubble constant value of H0 = 73 :3+1:7 1:8 km s 1 Mpc 1, describing deflector mass density profiles by either a power-law or stars (constant mass-to-light ratio) plus standar ...

Gravitationally lensed quasars can be used as powerful cosmological and astrophysical probes. We can (i) infer the Hubble constant H-0 based on the so-called time-delay technique, (ii) unveil substructures along the line-of-sight toward distant galaxies, a ...

Forthcoming imaging surveys will increase the number of known galaxy-scale strong lenses by several orders of magnitude. For this to happen, images of billions of galaxies will have to be inspected to identify potential candidates. In this context, deep-le ...

We present the HOLISMOKES programme on strong gravitational lensing of supernovae (SNe) as a probe of SN physics and cosmology. We investigate the effects of microlensing on early-phase SN Ia spectra using four different SN explosion models. We find that d ...

Euclid's photometric galaxy cluster survey has the potential to be a very competitive cosmological probe. The main cosmological probe with observations of clusters is their number count, within which the halo mass function (HMF) is a key theoretical quanti ...

The primary goals of the STRong lensing Insights into the Dark Energy Survey (STRIDES) collaboration are to measure the dark energy equation of state parameter and the free streaming length of dark matter. To this aim, STRIDES is discovering strongly lense ...

Context. The Euclid mission of the European Space Agency will perform a survey of weak lensing cosmic shear and galaxy clustering in order to constrain cosmological models and fundamental physics. Aims. We expand and adjust the mock Euclid likelihoods of t ...

Current and future imaging surveys require photometric redshifts (photo-zs) to be estimated for millions of galaxies. Improving the photo-z quality is a major challenge but is needed to advance our understanding of cosmology. In this paper we explore how t ...

Data from the Euclid space telescope will enable cosmic shear measurements to be carried out with very small statistical errors, necessitating a corresponding level of systematic error control. A common approach to correct for shear biases involves calibra ...

The ESA Euclid mission will survey more than 14 000 deg2 of the sky in visible and near-infrared wavelengths, mapping the extragalactic sky to constrain our cosmological model of the Universe. Although the survey focusses on regions further than 15 from th ...

We present the first VLT near-IR observations of a gravitationally lensed quasar, using adaptive optics and laser guide star. These observations can be considered as a test bench for future systematic observations of lensed quasars with adaptive optics, ev ...

Frédéric Courbin

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Euclid: The search for primordial features

H0LiCOW-IX. Cosmographic analysis of the doubly imaged quasar SDSS 1206+4332 and a new measurement of the Hubble constant

Euclid: Early Release Observations – Overview of the Perseus cluster and analysis of its luminosity and stellar mass functions

A PCA-based automated finder for galaxy-scale strong lenses

LXXI. Simulations and nonlinearities beyond ΛCDM. 3. Constraints on f(R) models from the photometric primary probes

Euclid: Identifying the reddest high-redshift galaxies in the Euclid Deep Fields with gradient-boosted trees

Time delay lens modelling challenge

STRIDES: a 3.9 per cent measurement of the Hubble constant from the strong lens system DES J0408-5354

Probing compact dark matter objects with microlensing in gravitationally lensed quasars

TDCOSMO. IV. Hierarchical time-delay cosmography - joint inference of the Hubble constant and galaxy density profiles

COSMOGRAIL: the COSmological MOnitoring of GRAvItational Lenses X. Modeling based on high-precision astrometry of a sample of 25 lensed quasars: consequences for ellipticity, shear, and astrometric anomalies

Euclid preparation XXXIII. Characterization of convolutional neural networks for the identification of galaxy-galaxy strong-lensing events

HOLISMOKES: I. Highly Optimised Lensing Investigations of Supernovae, Microlensing Objects, and Kinematics of Ellipticals and Spirals

Euclid preparation XXIV. Calibration of the halo mass function in λ(ν)CDM cosmologies

The STRong lensing Insights into the Dark Energy Survey (STRIDES) 2016 follow-up campaign - I. Overview and classification of candidates selected by two techniques

Euclid: Validation of the MontePython forecasting tools

The PAU Survey and Euclid: Improving broadband photometric redshifts with multi-task learning star

Euclid preparation LX. The use of HST images as input for weak-lensing image simulations

Euclid: Detecting Solar System objects in Euclid images and classifying them using Kohonen self-organising maps

A sharp look at the gravitationally lensed quasar SDSS J0806+2006 with laser guide star adaptive optics at the VLT