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astro-ph.CO2026

Euclid. A two-point correlation approach to diagnosing star-related systematics in the Euclid spectroscopic survey

Euclid Collaboration, I. Risso, B. R. Granett +298

The Euclid spectroscopic survey will measure galaxy clustering with unprecedented precision, requiring stringent control of observational and instrumental systematics. Star-related…

astro-ph.CO2026

Euclid preparation. The shape of halo profiles in CDM and non-standard cosmologies

Euclid Collaboration, L. Pizzuti, G. Y. Ferron +304

We study the shape of three-dimensional and projected dark-matter halo profiles extracted from cosmological -body simulations in CDM and non-standard cosmologies, using the \…

astro-ph.CO2026

Selection effects in correlated observations with application to distance-ladder observations

Will J. Percival

For over a century, following the work of Eddington, Kapteyn, Malmquist and others, astronomers have wrestled with selection biases when making inferences from samples of objects.…

astro-ph.CO2026

Euclid: Precise inference of defocus wavefront error from image diffraction spike measurements

D. Neumann, L. Miller, H. Hoekstra +146

The success of the Euclid cosmological weak lensing measurements requires unprecedented knowledge of the point spread function (PSF) shape. Defocus wavefront errors induce variatio…

astro-ph.CO2026

Euclid preparation. First investigation of the impact of cross-contamination on spectroscopic redshift measurements with pixel-level simulations

Euclid Collaboration, F. Passalacqua, S. Anselmi +299

We present a study on simulated data focused on understanding the performance of the spectroscopic redshift measurements with the Near-Infrared Spectrometer and Photometer (NISP) i…

astro-ph.CO2026

Euclid: Quick Data Release (Q1) -- LensMC shear measurement catalogue for cluster lensing science

G. Congedo, M. Sereno, H. Miyatake +140

We present a LensMC lensing analysis of Euclid Quick Release 1 images that were made available in March 2025. We measured shapes, positions, weights, and other morphological parame…

astro-ph.CO2026

Tracing the dynamical states and mass accretion histories of galaxy clusters in IllustrisTNG

Rashaad Reid, Syeda Lammim Ahad, Roan Haggar +2

As the largest and most recently formed stage of hierarchical structure, present-day galaxy clusters are predicted to have a broad range of late-time assembly histories. This diver…

astro-ph.CO2026

Euclid preparation. Three-dimensional galaxy clustering in configuration space: Three-point correlation function estimation

Euclid Collaboration, A. Veropalumbo, M. Moresco +303

Higher-order correlation functions are firmly established as a fundamental tool for the statistical analysis of clustering in modern galaxy surveys. It was demonstrated that they g…

astro-ph.CO2026

Euclid preparation. CosmoPostProcess: A simulation calibrated framework for weak lensing selection bias in richness-selected galaxy clusters

Euclid Collaboration, R. Ingrao, M. Costanzi +280

We present \texttt{CosmoPostProcess}, a simulation-based forward-modelling algorithm calibrated to reproduce Euclid optical cluster observables. Its main deliverable is a correctio…

astro-ph.CO2026

Euclid preparation. Refining input galaxy shape distributions for shear calibration simulations

Euclid Collaboration, H. Jansen, N. Martinet +282

The Euclid Wide Survey (EWS) will cover the majority of the extragalactic sky with a resolution similar to the Hubble Space Telescope. This unprecedented data set will introduce a…

astro-ph.CO2026

Euclid preparation. Galaxy power spectrum and bispectrum modelling

Euclid Collaboration, K. Pardede, A. Eggemeier +306

Higher-order correlation functions of the large-scale galaxy distribution offer access to information beyond that contained in standard 2-point statistics such as the power spectru…

astro-ph.CO2026

Propagating data-driven galaxy redshift distribution uncertainties in 32-pt analyses

Jaime Ruiz-Zapatero, Qianjun Hang, Yun-Hao Zhang +7

Uncertainties in the radial distribution of galaxies, , are one of the major contributions to the error budget of early Stage-IV galaxy survey analy…

astro-ph.CO2026★ 1 cited

Euclid. Populating a dark universe with galaxies using SciPIC

Euclid Collaboration, E. J. Gonzalez, J. Carretero +305

High-fidelity galaxy mocks are crucial for validating analysis pipelines and for cosmological inference. In this context, the Science Pipeline at PIC (SciPIC) is a pipeline specifi…

astro-ph.CO2026

Euclid preparation. Impact of redshift distribution uncertainties on the joint analysis of photometric galaxy clustering and weak gravitational lensing

Euclid Collaboration, K. A. Bertmann, A. Porredon +290

One of the mission's key projects is the so-called 32pt analysis, that is, the combination of cosmic shear, photometric galaxy clustering, and galaxy-gala…

astro-ph.CO2026★ 1 cited

Euclid preparation. Simulated galaxy catalogues for non-standard cosmological models

Euclid Collaboration, M. -A. Breton, P. Fosalba +289

Stage-IV galaxy surveys will provide the opportunity to test cosmological models and the underlying theory of gravity with unparalleled precision. In this context, it is crucial fo…

astro-ph.CO2026

DESI DR2 Baryon Acoustic Oscillations from the Lyman Alpha Forest Multipoles

N. G. Karaçaylı, A. Cuceu, J. Aguilar +55

We present an alternative measurement of the Baryon Acoustic Oscillation (BAO) using the Legendre multipole representation of the Ly forest correlation functions from the second…

astro-ph.CO2026

Emulating galaxy and peculiar velocity clustering on non-linear scales

T. Dumerchat, J. Bautista, C. Ravoux +37

We explore the potential of cross-correlating galaxies and peculiar velocities on non-linear scales to enhance cosmological constraints. Leveraging the \textsc{AbacusSummit} simula…

astro-ph.CO2026

Euclid preparation. CIV. Impact of galaxy intrinsic alignment modelling choices on Euclid 3x2pt cosmology

Euclid Collaboration, D. Navarro-Gironés, I. Tutusaus +274

The Euclid galaxy survey will provide unprecedented constraints on cosmology, but achieving unbiased results will require an optimal characterisation and mitigation of systematic e…

astro-ph.CO2026★ 3 cited

The DESI DR1 Peculiar Velocity Survey: growth rate measurements from the maximum likelihood fields method

Y. Lai, C. Howlett, J. Aguilar +60

We present the constraint on the growth rate of structure from the combination of DESI DR1 BGS sample, Fundamental Plane, and Tully-Fisher peculiar velocity catalogues using the ma…

astro-ph.CO2026

Dark Energy Survey Year 6 Results: Weak Lensing and Galaxy Clustering Cosmological Analysis Framework

D. Sanchez-Cid, A. Ferté, J. Blazek +115

We present the methodology for the weak lensing and galaxy clustering analyses of the Dark Energy Survey (DES) Year 6 data set. In this work, we design and validate the analysis pi…

astro-ph.CO2026

Euclid: Galaxy SED reconstruction in the PHZ processing function: impact on the PSF and the role of medium-band filters

Euclid Collaboration, F. Tarsitano, C. Schreiber +301

Weak lensing surveys require accurate correction for the point spread function (PSF) when measuring galaxy shapes. For a diffraction-limited PSF, as arises in space-based missions,…

astro-ph.CO2026

Euclid preparation. Calibrated intrinsic galaxy alignments in the Euclid Flagship simulation

Euclid Collaboration, K. Hoffmann, R. Paviot +298

Intrinsic alignments of galaxies are potentially a major contaminant of cosmological analyses of weak gravitational lensing. We construct a semi-analytic model of galaxy ellipticit…

astro-ph.CO2026

Euclid preparation. Testing analytic models of galaxy intrinsic alignments in the Euclid Flagship simulation

Euclid Collaboration, R. Paviot, B. Joachimi +293

We model intrinsic alignments (IA) in Euclid's Flagship simulation to investigate its impact on Euclid's weak lensing signal. Our IA implementation in the Flagship simulation takes…

astro-ph.CO2026

Euclid preparation. Galaxy 2-point correlation function modelling in redshift space

Euclid Collaboration, M. Kärcher, M. -A. Breton +309

The Euclid satellite will measure spectroscopic redshifts for tens of millions of emission-line galaxies. In the context of Stage-IV surveys, the 3-dimensional clustering of galaxi…