Publications associées à Advancements in Spectroscopic Surveys and Simulation Techniques in Physical Cosmology

Publications associées (22)

Fiducial-cosmology-dependent systematics for the DESI 2024 BAO analysis

Jiaxi Yu, Antoine Philippe Jacques Rocher

When measuring the Baryon Acoustic Oscillations (BAO) scale from galaxy surveys, one typically assumes a fiducial cosmology when converting redshift measurements into comoving distances and also when defining input parameters for the reconstruction algorit ...

IOP Publishing Ltd2025

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

Frédéric Courbin, Georges Meylan

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 ...

2025

DESI 2024 III: baryon acoustic oscillations from galaxies and quasars

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

We present the DESI 2024 galaxy and quasar baryon acoustic oscillations (BAO) measurements using over 5.7 million unique galaxy and quasar redshifts in the range 0.1 < z < 2.1. Divided by tracer type, we utilize 300,017 galaxies from the magnitude-limited ...

2025

Euclid preparation: LXX. Forecasting detection limits for intracluster light in the Euclid Wide Survey

Georges Meylan

The intracluster light (ICL) permeating galaxy clusters is a tracer of the cluster assembly history and potentially a tracer of their dark matter structure. In this work, we explore the capability of the Euclid Wide Survey to detect ICL using HE-band mock ...

EDP Sciences SA2025

Euclid II. The VIS instrument

Frédéric Courbin, Georges Meylan

This paper presents the specification, design, and development of the Visible Camera (VIS) on the European Space Agency’s Euclid mission. VIS is a large optical-band imager with a field of view of 0.54 deg2 sampled at 000 . 1 with an array of 609 Megapixel ...

2025

Distinct origins of environmentally quenched galaxies in the core and outer virialised regions of massive clusters at 0.8 &lt; z &lt; 1.5

Yannick Michael Bahé

High-redshift (

z

∼ 1) galaxy clusters are the domain where environmental quenching mechanisms are expected to emerge as important factors in the evolution of the quiescent galaxy population. Uncovering these initially subtle effects requires exploring mu ...

Oxford University Press (OUP)2025

DESI 2024 IV: Baryon Acoustic Oscillations from the Lyman alpha forest

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

We present the measurement of Baryon Acoustic Oscillations (BAO) from the Lyman- a (Lya) forest of high-redshift quasars with the first-year dataset of the Dark Energy Spectroscopic Instrument (DESI). Our analysis uses over 420 000 Lya forest spectra and t ...

IOP Publishing Ltd2025

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

Frédéric Courbin, Georges Meylan

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 ...

2025

BEACON: JWST NIRCam Pure-parallel Imaging Survey. I. Survey Design and Initial Results

Yannick Michael Bahé

We introduce the Bias-free Extragalactic Analysis for Cosmic Origins with NIRCam (BEACON) survey, a JWST Cycle 2 program allocated up to 600 pure-parallel hours of observations. BEACON explores high-latitude areas of the sky with JWST/NIRCam over ∼100 inde ...

2025

Rubies: Jwst/nirspec Confirmation of an Infrared-luminous, Broad-line Little Red Dot with an Ionized Outflow

Michaela Hirschmann

The JWST discovery of "little red dots" (LRDs) is reshaping our picture of the early Universe, yet the physical mechanisms driving their compact size and UV-optical colors remain elusive. Here, we report an unusually bright LRD (zspec = 3.1) observed as pa ...

IOP Publishing Ltd2025

Development of a dynamic-mesh porosity transport model for multi-dimensional fuel performance codes

Andreas Pautz, Alessandro Scolaro, Edoardo Luciano Brunetto

The porosity redistribution within nuclear fuel pellets exposed to high power ratings plays a critical role in the thermo-mechanical behavior of fast reactor fuel. Traditional fuel performance codes predict porosity migration through advection-dominated tr ...

2025

Evolution of the UV slope of galaxies at cosmic morning (z > 4): The properties of extremely blue galaxies

Michaela Hirschmann

We present an analysis of the UV continuum slope, β, using a sample of 726 galaxies with z > 4, selected from a mixture of JWST ERS, GTO, and GO observational programs. We considered only spectroscopic data obtained with the low-resolution (R ∼ 30−300) PRI ...

2025

The Cosmic Evolution Early Release Science Survey (CEERS)

Michaela Hirschmann

We present the Cosmic Evolution Early Release Science (CEERS) Survey, a 77.2 hr Director’s Discretionary Early Release Science Program. CEERS demonstrates, tests, and validates efficient extragalactic surveys using coordinated, overlapping parallel observa ...

2025

Cartesian and spherical multipole expansions in anisotropic media

Farhad Rachidi-Haeri, Marcos Rubinstein, Elias Per Joachim Le Boudec, Jose Felix Vega Stavro, Thomas Chaumont

The multipole expansion, a ubiquitous tool in a variety of physical problems, can be formulated in spherical and Cartesian coordinates. By constructing an explicit map linking both formulations in isotropic media, we discover a lack of equivalence between ...

Springer Science and Business Media LLC2025

The phase-space distribution of the M 81 satellite system

Oliver Müller, Nick Heesters

The spatial distribution of dwarf galaxies around their host galaxies is a critical test for the standard model of cosmology because it probes the dynamics of dark matter halos and is independent of the internal baryonic processes of galaxies. Comoving pla ...

Edp Sciences S A2024

Euclid preparation XLVIII. The pre-launch Science Ground Segment simulation framework

Frédéric Courbin, Georges Meylan, Benjamin Yvan Alexandre Clement

Context. The European Space Agency’s Euclid mission is one of a raft of forthcoming large-scale cosmology surveys that will map the large-scale structure in the Universe with unprecedented precision. The mission will collect a vast amount of data that will ...

2024

Lyα Emission Line Profiles of Extreme [O iii]- emitting Galaxies at z ≳ 2: Implications for Lyα Visibility in the Reionization Era

Adèle Marie Françoise Plat

JWST observations have recently begun delivering the first samples of Lyα velocity profile measurements at z > 6, opening a new window into the reionization process. Interpretation of z ≳ 6 line profiles is currently stunted by limitations in our knowledge ...

2024

The AGORA High-resolution Galaxy Simulations Comparison Project. VI. Similarities and Differences in the Circumgalactic Medium

Yves Revaz

We analyze the circumgalactic medium (CGM) for eight commonly-used cosmological codes in the AGORA collaboration. The codes are calibrated to use identical initial conditions, cosmology, heating and cooling, and star formation thresholds, but each evolves ...

Iop Publishing Ltd2024

Weak gravitational lensing measurements of Abell 2744 using JWST and shear measurement algorithm pyRRG-JWST

David Richard Harvey

We update the publicly available weak lensing shear measurement algorithm pyRRG for the JWST, and apply it to UNCOVER DR1 imaging of galaxy cluster Abell 2744. At short wavelengths (

Oxford Univ Press2024

Strong gravitational lensing's 'external shear' is not shear

David Richard Harvey

The distribution of mass in galaxy-scale strong gravitational lenses is often modelled as an elliptical power-law plus 'external shear', which notionally accounts for neighbouring galaxies and cosmic shear along our line of sight. A small amount of externa ...

Oxford Univ Press2024