Publications associées à Galaxy Alignments: Theory, Modelling & Simulations

Publications associées (48)

The AGORA High-Resolution Galaxy Simulations Comparison Project VII. Satellite quenching in zoom-in simulation of a Milky Way-mass halo

Context. Satellite galaxies experience multiple physical processes when interacting with their host halos, often leading to the quenching of star formation. In the Local Group, satellite quenching has been shown to be highly efficient, affecting nearly all ...

2025

Euclid preparation: LXV. Determining the weak lensing mass accuracy and precision for galaxy clusters

Frédéric Courbin, Georges Meylan

The ability to measure unbiased weak-lensing (WL) masses is a key ingredient to exploit galaxy clusters as a competitive cosmological probe with the ESA Euclid survey or future missions. We investigate the level of accuracy and precision of cluster masses ...

2025

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

Frédéric Courbin, Georges Meylan

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 ...

2025

Euclid: Early Release Observations of diffuse stellar structures and globular clusters as probes of the mass assembly of galaxies in the Dorado group?

Georges Meylan, Olivia Mueller

Deep surveys have helped to unveil the history of past and present galaxy mergers, and, in particular, uncovering their tidal debris and co-located globular clusters (GCs). Euclid’s unique combination of capabilities (spatial resolution, depth, and wide sk ...

2025

SCUBADive. I. JWST plus ALMA Analysis of 289 Submillimeter Galaxies in COSMOS-web

Michaela Hirschmann

JWST has enabled detecting and spatially resolving the heavily dust-attenuated stellar populations of submillimeter galaxies, revealing detail that was previously inaccessible. In this work, we construct a sample of 289 submillimeter galaxies with joint At ...

IOP Publishing Ltd2025

Intergalactic magnetism in a γ -ray beam as a model of Porphyrion

Andrii Neronov

We estimate the magnetic field in the jets of the recently discovered 7 Mpc long Porphyrion system. We used nondetection of the system in gamma-rays to derive a lower bound on the co-moving magnetic field strength at the level of 10 nG (comoving). This val ...

2025

Euclid and KiDS-1000: Quantifying the impact of source-lens clustering on cosmic shear analyses

Frédéric Courbin, Georges Meylan

Cosmic shear is a powerful probe of cosmological models and the transition from current Stage-III surveys such as the Kilo-Degree Survey (KiDS) to the increased area and redshift range of Stage IV surveys such as Euclid will significantly increase the prec ...

2025

Impact and mitigation of spectroscopic systematics on DESI DR1 clustering measurements

Jiaxi Yu

The large scale structure catalogs within DESI Data Release 1 (DR1) use nearly 6 million galaxies and quasars as tracers of the large-scale structure of the universe to measure the expansion history with baryon acoustic oscillations and the growth of struc ...

IOP Publishing Ltd2025

Analytical and EZmock covariance validation for the DESI 2024 results

Jiaxi Yu, Daniel Felipe Forero Sanchez

The estimation of uncertainties in cosmological parameters is an important challenge in Large-Scale-Structure (LSS) analyses. For standard analyses such as Baryon Acoustic Oscillations (BAO) and Full-Shape two approaches are usually considered. First: anal ...

2025

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

Frédéric Courbin, Georges Meylan

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 ...

2025

Euclid: Early Release Observations – Deep anatomy of nearby galaxies

Frédéric Courbin, Georges Meylan, Pascale Jablonka

Euclid is poised to make significant advances in the study of nearby galaxies in the Local Universe. Here we present a first look at six galaxies observed for the Nearby Galaxy Showcase as part of the Euclid Early Release Observations acquired between Augu ...

2025

Hydrodynamical simulations of merging galaxy clusters: giant dark matter particle colliders, powered by gravity

David Richard Harvey

Terrestrial particle accelerators collide charged particles, then watch the trajectory of outgoing debris - but they cannot manipulate dark matter. Fortunately, dark matter is the main component of galaxy clusters, which are continuously pulled together by ...

Oxford Univ Press2024

Desi 2024 Vi: Cosmological Constraints From the Measurements of Baryon Acoustic Oscillations

Jiaxi Yu, Daniel Felipe Forero Sanchez, Antoine Philippe Jacques Rocher

We present cosmological results from the measurement of baryon acoustic oscillations (BAO) in galaxy, quasar and Lyman-alpha forest tracers from the first year of observations from the Dark Energy Spectroscopic Instrument (DESI), to be released in the DESI ...

IOP Publishing Ltd2025

The AGORA High-resolution Galaxy Simulations Comparison Project. V. Satellite Galaxy Populations in a Cosmological Zoom-in Simulation of a Milky Way-Mass Halo

Yves Revaz, Loïc Hausammann

We analyze and compare the satellite halo populations at z similar to 2 in the high-resolution cosmological zoom-in simulations of a 1012 M circle dot target halo (z = 0 mass) carried out on eight widely used astrophysical simulation codes (Art-I, Enzo, Ra ...

Iop Publishing Ltd2024

Euclid preparation: LVIII. Detecting extragalactic globular clusters in the Euclid survey

Frédéric Courbin, Georges Meylan

Extragalactic globular clusters (EGCs) are an abundant and powerful tracer of galaxy dynamics and formation, and their own formation and evolution is also a matter of extensive debate. The compact nature of globular clusters means that they are hard to spa ...

2025

Extremely Red Galaxies at z=5-9 with MIRI and NIRSpec: Dusty Galaxies or Obscured Active Galactic Nuclei?

Michaela Hirschmann

We study a new population of extremely red objects (EROs) recently discovered by the James Webb Space Telescope (JWST) based on their NIRCam colors F277W - F444W > 1.5 mag. We find 37 EROs in the Cosmic Evolution Early Release Science Survey (CEERS) field ...

Iop Publishing Ltd2024

Euclid: Early Release Observations The intracluster light of Abell 2390

Georges Meylan

Intracluster light (ICL) provides a record of the dynamical interactions undergone by clusters, giving clues on cluster formation and evolution. Here, we analyse the properties of ICL in the massive cluster Abell 2390 at redshift z = 0.228. Our analysis is ...

2025

XXXIV. The effect of linear redshift-space distortions in photometric galaxy clustering and its cross-correlation with cosmic shear

Maurizio Martinelli, Frédéric Courbin, Georges Meylan, Malte Tewes, Slobodan Ilic, Gianluca Castignani, Alessandro Pezzotta

Context. The cosmological surveys that are planned for the current decade will provide us with unparalleled observations of the distribution of galaxies on cosmic scales, by means of which we can probe the underlying large-scale structure (LSS) of the Univ ...

Edp Sciences S A2024

3d Cmz. I. Central Molecular Zone Overview

Robin Gopala Tress

The Central Molecular Zone (CMZ) is the largest reservoir of dense molecular gas in the Galaxy and is heavily obscured in the optical and near-IR. We present an overview of the far-IR dust continuum, where the molecular clouds are revealed, provided by Her ...

IOP Publishing Ltd2025

Swift : a modern highly parallel gravity and smoothed particle hydrodynamics solver for astrophysical and cosmological applications

Yves Revaz, Yannick Michael Bahé, Loïc Hausammann, Mladen Ivkovic

Numerical simulations have become one of the key tools used by theorists in all the fields of astrophysics and cosmology. The development of modern tools that target the largest existing computing systems and exploit state-of-the-art numerical methods and ...

2024