Publications de Austin Chandler Peel

Euclid I. Overview of the Euclid mission

Yves Revaz, Georges Meylan, Frédéric Courbin, Pascale Jablonka, Jean-Paul Richard Kneib, Austin Chandler Peel, Michaela Hirschmann, Lucie Anemone Scharré

The current standard model of cosmology successfully describes a variety of measurements, but the nature of its main ingredients, dark matter and dark energy, remains unknown. Euclid is a medium-class mission in the Cosmic Vision 2015–2025 programme of the ...

2025

Euclid preparation: LIII. LensMC, weak lensing cosmic shear measurement with forward modelling and Markov Chain Monte Carlo sampling

Georges Meylan, Frédéric Courbin, Austin Chandler Peel

LENSMC is a weak lensing shear measurement method developed for Euclid and Stage-IV surveys. It is based on forward modelling in order to deal with convolution by a point spread function (PSF) with comparable size to many galaxies, sampling the posterior d ...

2024

Microlensing of Strongly Lensed Quasars

Martin Raoul Robert Millon, Austin Chandler Peel, Georgios Vernardos

Strong gravitational lensing of quasars has the potential to unlock the poorly understood physics of these fascinating objects, as well as serve as a probe of the lensing mass distribution and of cosmological parameters. In particular, gravitational microl ...

Springer2024

Euclid preparation XXXII. Evaluating the weak-lensing cluster mass biases using the Three Hundred Project hydrodynamical simulations

Georges Meylan, Frédéric Courbin, Austin Chandler Peel

The photometric catalogue of galaxy clusters extracted from ESA Euclid data is expected to be very competitive for cosmological studies. Using dedicated hydrodynamical simulations, we present systematic analyses simulating the expected weak-lensing profile ...

Edp Sciences S A2024

Euclid preparation XXXVI. Modelling the weak lensing angular power spectrum

Georges Meylan, Frédéric Courbin, Fabio Finelli, Richard Massey, Maurizio Martinelli, Gianluca Castignani, Marcello Farina, Austin Chandler Peel, Yi Wang

This work considers which higher order modeling e ffects on the cosmic shear angular power spectra must be taken into account for Euclid. We identified the relevant terms and quantified their individual and cumulative impact on the cosmological parameter i ...

Edp Sciences S A2024

Euclid preparation: XLII. A unified catalogue-level reanalysis of weak lensing by galaxy clusters in five imaging surveys

Georges Meylan, Frédéric Courbin, Austin Chandler Peel

Precise and accurate mass calibration is required to exploit galaxy clusters as astrophysical and cosmological probes in the Euclid era. Systematic errors in lensing signals by galaxy clusters can be empirically estimated by comparing different surveys wit ...

2024

Euclid preparation XLIII. Measuring detailed galaxy morphologies for Euclid with machine learning

Georges Meylan, Frédéric Courbin, Austin Chandler Peel

The Euclid mission is expected to image millions of galaxies at high resolution, providing an extensive dataset with which to study galaxy evolution. Because galaxy morphology is both a fundamental parameter and one that is hard to determine for large samp ...

2024

Euclid preparation - XXIII. Derivation of galaxy physical properties with deep machine learning using mock fluxes and H-band images

Robin Humphry-Baker, Georges Meylan, Frédéric Courbin, Richard Massey, Maurizio Martinelli, Gianluca Castignani, Marcello Farina, Austin Chandler Peel, Yi Wang

Next-generation telescopes, like Euclid, Rubin/LSST, and Roman, will open new windows on the Universe, allowing us to infer physical properties for tens of millions of galaxies. Machine-learning methods are increasingly becoming the most efficient tools to ...

OXFORD UNIV PRESS2023

SKA Science Data Challenge 2: analysis and results

Frédéric Courbin, Xiuwei Zhang, Hua Zhang, Libo Yu, Jean-Paul Richard Kneib, Aymeric Alexandre Galan, Yi Zhang, Lei Zhang, Jean-Luc Starck, Claudio Gheller, Austin Chandler Peel, Emma Elizabeth Tolley, Mark Thomas Sargent, Yi Wang, Xin Chen

The Square Kilometre Array Observatory (SKAO) will explore the radio sky to new depths in order to conduct transformational science. SKAO data products made available to astronomers will be correspondingly large and complex, requiring the application of ad ...

OXFORD UNIV PRESS2023

Euclid preparation XXII. Selection of quiescent galaxies from mock photometry using machine learning

Georges Meylan, Frédéric Courbin, Fabio Finelli, Richard Massey, Maurizio Martinelli, Gianluca Castignani, Marcello Farina, Austin Chandler Peel, Yi Wang

The Euclid Space Telescope will provide deep imaging at optical and near-infrared wavelengths, along with slitless near-infrared spectroscopy, across similar to 15 000deg(2) of the sky. Euclid is expected to detect similar to 12 billion astronomical source ...

EDP SCIENCES S A2023

Euclid preparation: XXVIII. Forecasts for ten different higher-order weak lensing statistics

Frédéric Courbin, Fabio Finelli, Richard Massey, Maurizio Martinelli, Jean-Luc Starck, Gianluca Castignani, Marcello Farina, Austin Chandler Peel, Yi Wang

Recent cosmic shear studies have shown that higher-order statistics (HOS) developed by independent teams now outperform standard two-point estimators in terms of statistical precision thanks to their sensitivity to the non-Gaussian features of large-scale ...

EDP SCIENCES S A2023

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

Slobodan Ilic, Georges Meylan, Frédéric Courbin, Fabio Finelli, Maurizio Martinelli, Gianluca Castignani, Marcello Farina, Austin Chandler Peel, Yi Wang

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 ...

EDP SCIENCES S A2023

JAX-COSMO: AN END-TO-END DIFFERENTIABLE AND GPU ACCELERATED COSMOLOGY LIBRARY

Austin Chandler Peel

We present jax-cosmo, a library for automatically differentiable cosmological theory calculations. jax-cosmo uses the JAX library, which has created a new coding ecosystem, especially in probabilistic programming. As well as batch acceleration, just-in-tim ...

2023

Lightweight HI source finding for next generation radio surveys

Frédéric Courbin, Jean-Paul Richard Kneib, Aymeric Alexandre Galan, Austin Chandler Peel, Emma Elizabeth Tolley, Mark Thomas Sargent

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 ...

ELSEVIER2022

Using wavelets to capture deviations from smoothness in galaxy-scale strong lenses

Frédéric Courbin, Aymeric Alexandre Galan, Austin Chandler Peel, Georgios Vernardos

Modeling the mass distribution of galaxy-scale strong gravitational lenses is a task of increasing difficulty. The high-resolution and depth of imaging data now available render simple analytical forms ineffective at capturing lens structures spanning a la ...

EDP SCIENCES S A2022

Euclid preparation XXI. Intermediate-redshift contaminants in the search for z > 6 galaxies within the Euclid Deep Survey

Georges Meylan, Frédéric Courbin, Hakim Atek, Richard Massey, Maurizio Martinelli, Jean-Luc Starck, Gianluca Castignani, Marcello Farina, Austin Chandler Peel, Yi Wang

Context. The Euclid mission is expected to discover thousands of z > 6 galaxies in three deep fields, which together will cover a similar to 50 deg(2) area. However, the limited number of Euclid bands (four) and the low availability of ancillary data could ...

EDP SCIENCES S A2022

ShapePipe: A modular weak-lensing processing and analysis pipeline

Jean-Luc Starck, Austin Chandler Peel

We present the first public release of ShapePipe, an open-source and modular weak-lensing measurement, analysis, and validation pipeline written in Python. We describe the design of the software and justify the choices made. We provide a brief description ...

2022

Euclid preparation XVIII. The NISP photometric system

Georges Meylan, Frédéric Courbin, Austin Chandler Peel

Euclid will be the first space mission to survey most of the extragalactic sky in the 0.95-2.02 mu m range, to a 5 sigma point-source median depth of 24.4 AB mag. This unique photometric dataset will find wide use beyond Euclid's core science. In this pape ...

EDP SCIENCES S A2022

ShapePipe: A new shape measurement pipeline and weak-lensing application to UNIONS/CFIS data

Jean-Luc Starck, Austin Chandler Peel

Context. The Ultraviolet Near-Infrared Optical Northern Survey (UNIONS) is an ongoing collaboration that will provide the largest deep photometric survey of the northern sky in four optical bands to date. As part of this collaboration, the Canada-France Im ...

EDP SCIENCES S A2022

SLITRONOMY: Towards a fully wavelet-based strong lensing inversion technique

Frédéric Courbin, Aymeric Alexandre Galan, Rémy Elie Joseph, Austin Chandler Peel

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