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Publications associées (32)

TDCOSMO I. An exploration of systematic uncertainties in the inference ofH(0)from time-delay cosmography

Frédéric Courbin

Strong-lensing time delays enable the measurement of the Hubble constant (H0) independently of other traditional methods. The main limitation to the precision of time-delay cosmography is mass-sheet degeneracy (MSD). Some of the previous TDCOSMO analyses b ...

EDP SCIENCES S A2023

Potential scientific synergies in weak lensing studies between the CSST and Euclid space probes

Jean-Paul Richard Kneib, Huanyuan Shan

Aims. With the next generation of large surveys poised to join the ranks of observational cosmology in the near future, it is important to explore their potential synergies and to maximize their scientific outcomes. In this study, we aim to investigate the ...

EDP SCIENCES S A2023

Euclid: Calibrating photometric redshifts with spectroscopic cross-correlations

Yi Wang, Frédéric Courbin, Georges Meylan

Cosmological constraints from key probes of the Euclid imaging survey rely critically on the accurate determination of the true redshift distributions, n(z); of tomographic redshift bins. We determine whether the mean redshift, < z >, of ten Euclid tomogra ...

EDP SCIENCES S A2023

First detection of the BAO signal from early DESI data

Cheng Zhao, Anand Stéphane Raichoor, David Schlegel, Andrei Variu

We present the first detection of the baryon acoustic oscillations (BAOs) signal obtained using unblinded data collected during the initial 2 months of operations of the Stage-IV ground-based Dark Energy Spectroscopic Instrument (DESI). From a selected sam ...

Oxford Univ Press2023

Void Lensing in Cubic Galileon Gravity

Cheng Zhao, Huanyuan Shan, Jiaxi Yu, Qiao Wang

Weak-lensing studies via cosmic voids are a promising probe of modified gravity (MG). The excess surface mass density (ESD) is widely used as a lensing statistic in weak-lensing research. In this paper, we use the ray-tracing method to study the ESD around ...

IOP Publishing Ltd2023

Fast correlation function calculator A high-performance pair-counting toolkit

Cheng Zhao

Context. A novel high-performance exact pair-counting toolkit called fast correlation function calculator (FCFC) is presented.Aims. With the rapid growth of modern cosmological datasets, the evaluation of correlation functions with observational and simula ...

EDP SCIENCES S A2023

Crowded No More: The Accuracy of the Hubble Constant Tested with High-resolution Observations of Cepheids by JWST

Richard Irving Anderson

High-resolution James Webb Space Telescope (JWST) observations can test confusion-limited Hubble Space Telescope (HST) observations for a photometric bias that could affect extragalactic Cepheids and the determination of the Hubble constant. We present JWS ...

Iop Publishing Ltd2023

Two Massive, Compact, and Dust-obscured Candidate z ≃ 8 Galaxies Discovered by JWST

Michaela Hirschmann

We present a search for extremely red, dust-obscured, z > 7 galaxies with JWST/NIRCam+MIRI imaging over the first 20 arcmin(2) of publicly available Cycle 1 data from the COSMOS-Web, CEERS, and PRIMER surveys. Based on their red color in F277W-F444W (simil ...

Iop Publishing Ltd2023

Cosmological Fisher forecasts for next-generation spectroscopic surveys

Jean-Paul Richard Kneib, Cheng Zhao, Jiaxi Yu

Next-generation spectroscopic surveys such as the MegaMapper, MUltiplexed Survey Telescope (MUST), MaunaKea Spectroscopic Explorer (MSE), and WideField Spectroscopic Telescope (WST) are foreseen to increase the number of galaxy/quasar redshifts by an order ...

OXFORD UNIV PRESS2023

DESI mock challenge Halo and galaxy catalogues with the bias assignment method

Cheng Zhao, Yu Yu, Ginevra Favole

Context. We present a novel approach to the construction of mock galaxy catalogues for large-scale structure analysis based on the distribution of dark matter halos obtained with effective bias models at the field level. Aims. We aim to produce mock galaxy ...

EDP SCIENCES S A2023

The DESI Survey Validation: Results from Visual Inspection of Bright Galaxies, Luminous Red Galaxies, and Emission-line Galaxies

Yi Zhang, Stewart Cole, Anand Stéphane Raichoor, Jiaxi Yu, Arjun Dey, Antoine Philippe Jacques Rocher

The Dark Energy Spectroscopic Instrument (DESI) Survey has obtained a set of spectroscopic measurements of galaxies to validate the final survey design and target selections. To assist in these tasks, we visually inspect DESI spectra of approximately 2500 ...

IOP Publishing Ltd2023

How much metal did the first stars provide to the ultra-faint dwarfs?

Pascale Jablonka, Yves Revaz, Mahsa Sanati, Fabien Nicolas Jeanquartier

Numerical simulations of dwarf galaxies have so far failed to reproduce the observed metallicity-luminosity relation, down to the regime of ultra-faint dwarfs (UFDs). We address this issue by exploring how the first generations of metal-free stars (Pop III ...

EDP SCIENCES S A2023