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Concept

Réionisation

Publications associées (32)

Void BAO measurements on quasars from eBOSS

Jean-Paul Richard Kneib, Cheng Zhao, Amélie Tamone, Andrei Variu, Daniel Felipe Forero Sanchez

We present the clustering of voids based on the quasar (QSO) sample of the extended Baryon Oscillation Spectroscopic Survey Data Release 16 in configuration space. We define voids as overlapping empty circumspheres computed by Delaunay tetrahedra spanned b ...

Oxford Univ Press2023

Emission-line properties of IllustrisTNG galaxies: from local diagnostic diagrams to high-redshift predictions for JWST

Michaela Hirschmann, Adèle Marie Françoise Plat

We compute synthetic, rest-frame optical and ultraviolet (UV) emission-line properties of galaxy populations at redshifts from z approximate to 0 to =8 in a full cosmological framework. We achieve this by coupling, in post-processing, the cosmological Illu ...

Oxford Univ Press2023

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

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

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

Removing systematics-induced 21-cm foreground residuals by cross-correlating filtered data

Tianyue Chen

Observations of the redshifted 21-cm signal emitted by neutral hydrogen represent a promising probe of large-scale structure in the universe. However, the cosmological 21-cm signal is challenging to observe due to astrophysical foregrounds which are severa ...

American Physical Society2022

J1721+8842: a gravitationally lensed binary quasar with a proximate damped Lyman-alpha absorber

Frédéric Courbin, Martin Raoul Robert Millon, Hung-Hsu Chan, Eric Gérard Guy Paic, Cameron Alexander Campbell Lemon

High-redshift binary quasars provide key insights into mergers and quasar activity, and are useful tools for probing the spatial kinematics and chemistry of galaxies along the line of sight. However, only three sub-10-kpc binaries have been confirmed above ...

EDP SCIENCES S A2022

The completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: cosmological implications from multitracer BAO analysis with galaxies and voids

Jean-Paul Richard Kneib, Cheng Zhao, Huanyuan Shan, Jiaxi Yu, Daniel Felipe Forero Sanchez, Amélie Tamone, Andrei Variu

We construct cosmic void catalogues with the DIVE void finder upon SDSS BOSS DR12 and eBOSS DR16 galaxy samples with BAO reconstruction, and perform a joint BAO analysis using different types of galaxies and the corresponding voids. The BAO peak is evident ...

OXFORD UNIV PRESS2022

H I constraints from the cross-correlation of eBOSS galaxies and Green Bank Telescope intensity maps

Jean-Paul Richard Kneib

We present the joint analysis of Neutral Hydrogen (H I) Intensity Mapping observations with three galaxy samples: the Luminous Red Galaxy (LRG) and Emission Line Galaxy (ELG) samples from the eBOSS survey, and the WiggleZ Dark Energy Survey sample. The H I ...

OXFORD UNIV PRESS2022

KiDS and Euclid: Cosmological implications of a pseudo angular power spectrum analysis of KiDS-1000 cosmic shear tomography

Yi Wang, Georges Meylan, Huanyuan Shan

We present a tomographic weak lensing analysis of the Kilo Degree Survey Data Release 4 (KiDS-1000), using a new pseudo angular power spectrum estimator (pseudo-C-l) under development for the ESA Euclid mission. Over 21 million galaxies with shape informat ...

EDP SCIENCES S A2022

The completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: a multitracer analysis in Fourier space for measuring the cosmic structure growth and expansion rate

Jean-Paul Richard Kneib, Cheng Zhao, Anand Stéphane Raichoor

We perform a joint BAO and RSD analysis using the eBOSS DR16 LRG and ELG samples in the redshift range of z is an element of [0.6, 1.1], and detect an RSD signal from the cross-power spectrum at a similar to 4 sigma confidence level, i.e., f sigma(8) = 0.3 ...

OXFORD UNIV PRESS2021

Deep optical spectroscopy of extended Ly alpha emission around three radio-quiet z=4.5 quasars

Frédéric Courbin, Pierre North, Alexander Patrick Eigenbrod

We report the first results of a spectroscopic search for Ly alpha envelopes around three z similar to 4.5 radio-quiet quasars. Our observational strategy adopts the FORS2 spectrograph mounted to the UT1 of the Very Large Telescope (VLT) in the multi-slit ...

2008