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1,343 papers · 1 filter

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

Euclid: Inferring star-formation history via cross-correlations of photometric clustering and shear with the cosmic infrared background

J. Han, S. Camera, M. Migliaccio +146

The cosmic infrared background, sourced by dust heated by star-forming activity, encodes the integrated history of the star-formation distribution over a large swathe of cosmic tim…

astro-ph.CO2026

Testing string theory with combined cosmological probes: a case study for dark matter gravitons

Alkistis Pourtsidou

The string theory Swampland programme has resulted in distinct scenarios for the particle nature of dark matter. In this research note, I use combined cosmological probes to constr…

astro-ph.CO2026

The heating rate of the Intergalactic Medium by Lyman- photon scattering

Avery Meiksin

The strength of the 21-cm Cosmic Dawn radio absorption signature against the Cosmic Microwave Background or against a bright background radio source depends on the temperature of t…

astro-ph.CO2026

Euclid: Measuring the intrinsic alignment of galaxies around cosmic voids in the \Euclid Flagship simulation\

P. Vielzeuf, M. -C. Cousinou, A. Pisani +149

We present a methodology to measure the intrinsic alignment (IA) signal of galaxies in the vicinity of cosmic voids using the \Euclid-like Flagship cosmological simulation from the…

astro-ph.CO2026

Quintom Model Perturbations

L. W. K. Goh, A. N. Taylor

We build upon the work of Goh and Taylor 2025, in which we proposed a two scalar field quintom framework capable of naturally realising a phantom-to-quintessence transition in the…

astro-ph.CO2026

The PAU Survey and Euclid: Analysing photometric redshifts from realistically simulated narrow-band photometry with Flagship 2

A. Wittje, H. Hildebrandt, D. Navarro-Gironés +154

The study of the large-scale structure of the Universe and the distribution of galaxies has been greatly advanced by the application of various types of photometric redshift estima…

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

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

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

Euclid: The linear-construction covariance and cosmology

V. Lindholm, E. Sihvola, J. Valiviita +137

We study the properties of galaxy cluster 2-point correlation function covariance matrices estimated using the linear-construction (LC) method, which is computationally up to 20 ti…

astro-ph.CO2026

Thermal enhancement of inflationary magnetic fields

Arjun Berera, Suddhasattwa Brahma, Zizang Qiu +1

We investigate primordial magnetogenesis by assuming the gauge field is prepared in a thermal state during inflation rather than the standard Bunch-Davies vacuum. The temperature $…

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

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★ 1 cited

KiDS-Legacy: WIMP dark matter constraints from the cross-correlation of weak lensing and Fermi-LAT gamma rays

Shiyang Zhang, Hendrik Hildebrandt, Ziang Yan +13

Dark matter dominates the matter content of the Universe, and its properties can be constrained through large-scale structure probes such as the cross-correlation between the unres…

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,…