Publications by Johan Richard | EPFL Graph Search

Probing the faint-end luminosity function of Lyman-alpha emitters at 3 < z < 7 behind 17 MUSE lensing clusters

Benjamin Yvan Alexandre Clement, Johan Richard

Context. This paper presents a study of the galaxy Lyman-alpha luminosity function (LF) using a large sample of 17 lensing clusters observed by the Multi Unit Spectroscopic Explorer (MUSE) at the ESO Very Large Telescope (VLT). The magnification resulting ...

Edp Sciences S A2023

A new step forward in realistic cluster lens mass modelling: analysis of Hubble Frontier Field Cluster Abell S1063 from joint lensing, X-ray, and galaxy kinematics data

Jean-Paul Richard Kneib, Benjamin Yvan Alexandre Clement, Benjamin Emmanuel Nicolas Beauchesne, Mathilde Jauzac, Johan Richard

We present a new method to simultaneously and self-consistently model the mass distribution of galaxy clusters that combines constraints from strong lensing features, X-ray emission, and galaxy kinematics measurements. We are able to successfully decompose ...

Oxford Univ Press2023

Revealing galaxy candidates out to z similar to 16 with JWST observations of the lensing cluster SMACS0723

Jean-Paul Richard Kneib, Hakim Atek, Johan Richard

One of the main goals of the JWST is to study the first galaxies in the Universe. We present a systematic photometric analysis of very distant galaxies in the first JWST deep field towards the massive lensing cluster SMACS0723. As a result, we report the d ...

OXFORD UNIV PRESS2023

Uncovering a population of gravitational lens galaxies with magnified standard candle SN Zwicky

Rémy Elie Joseph, Cameron Alexander Campbell Lemon, Johan Richard, Johannes Richard Cornelis Geerit Kruis

Detecting gravitationally lensed supernovae is among the biggest challenges in astronomy. It involves a combination of two very rare phenomena: catching the transient signal of a stellar explosion in a distant galaxy and observing it through a nearly perfe ...

NATURE PORTFOLIO2023

Improving parametric mass modelling of lensing clusters through a perturbative approach

Jean-Paul Richard Kneib, Benjamin Yvan Alexandre Clement, Benjamin Emmanuel Nicolas Beauchesne, Johan Richard

We present a new method to model the mass distribution of galaxy clusters that combines a parametric and a free-form approach to reconstruct cluster cores with strong lensing constraints. It aims at combining the advantages of both approaches, by keeping t ...

OXFORD UNIV PRESS2021

The BUFFALO HST Survey

Jean-Paul Richard Kneib, Pascale Jablonka, David Richard Harvey, Benjamin Yvan Alexandre Clement, Mathilde Jauzac, Huanyuan Shan, Hakim Atek, Anja Von der Linden, Matthieu Schaller, Céline Tchernin

The Beyond Ultra-deep Frontier Fields and Legacy Observations (BUFFALO) is a 101 orbit + 101 parallel Cycle 25 Hubble Space Telescope (HST) Treasury program taking data from 2018 to 2020. BUFFALO will expand existing coverage of the Hubble Frontier Fields ...

IOP PUBLISHING LTD2020

The core of the massive cluster merger MACS J0417.5-1154 as seen by VLT/MUSE

Jean-Paul Richard Kneib, David Richard Harvey, Johannes Richard Cornelis Geerit Kruis, Mathilde Jauzac, Richard Massey, Johan Richard

We present a multiwavelength analysis of the core of the massive galaxy cluster MACS J0417.5-1154 (z = 0.441). Our analysis takes advantage of Very Large Telescope/Multi-Unit Spectroscopic Explorer observations which allowthe spectroscopic confirmation of ...

OXFORD UNIV PRESS2019

Molecular clouds in the Cosmic Snake normal star-forming galaxy 8 billion years ago

Jean-Paul Richard Kneib, Daniel Pfenniger, Johan Richard

The cold molecular gas in contemporary galaxies is structured in discrete cloud complexes. These giant molecular clouds (GMCs), with 10(4)-10(7) solar masses (M-circle dot) and radii of 5-100 parsecs, are the seeds of star formation(1). Highlighting the mo ...

NATURE PUBLISHING GROUP2019

Dark matter dynamics in Abell 3827: new data consistent with standard cold dark matter

Frédéric Courbin, David Richard Harvey, Mathilde Jauzac, Rémy Elie Joseph, Richard Massey, Johan Richard

2018

Searching for supernovae in the multiply-imaged galaxies behind the gravitational telescope A370

Jean-Paul Richard Kneib, Johan Richard

2018