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Publications associées (32)

Deep learning approach for identification of H II regions during reionization in 21-cm observations - II. Foreground contamination

Jean-Paul Richard Kneib, Emma Elizabeth Tolley, Michele Bianco, Tianyue Chen

The upcoming Square Kilometre Array Observatory will produce images of neutral hydrogen distribution during the epoch of reionization by observing the corresponding 21-cm signal. However, the 21-cm signal will be subject to instrumental limitations such as ...

Oxford Univ Press2024

Validation of the Scientific Program for the Dark Energy Spectroscopic Instrument

Hua Zhang, Stewart Cole, Xin Chen, Sun Hee Kim, Jean-Paul Richard Kneib, Eduardo Sanchez, Cheng Zhao, Anand Stéphane Raichoor, David Schlegel, Zhifeng Ding, Jiangyan Yang, Daniel Felipe Forero Sanchez, Zheng Zheng, Andrei Variu, Arjun Dey, Antoine Philippe Jacques Rocher

The Dark Energy Spectroscopic Instrument (DESI) was designed to conduct a survey covering 14,000 deg(2) over 5 yr to constrain the cosmic expansion history through precise measurements of baryon acoustic oscillations (BAO). The scientific program for DESI ...

Iop Publishing Ltd2024

An Atlas of Color-selected Quiescent Galaxies at z > 3 in Public JWST Fields

Michaela Hirschmann, Minju Lee

We present the results of a systematic search for candidate quiescent galaxies in the distant universe in 11 JWST fields with publicly available observations collected during the first 3 months of operations and covering an effective sky area of similar to ...

IOP Publishing Ltd2023

Performance of the Quasar Spectral Templates for the Dark Energy Spectroscopic Instrument

Jiaxi Yu, Zheng Zheng

Millions of quasar spectra will be collected by the Dark Energy Spectroscopic Instrument (DESI), leading to a fourfold increase in the number of known quasars. High-accuracy quasar classification is essential to tighten constraints on cosmological paramete ...

IOP Publishing Ltd2023

A Long Time Ago in a Galaxy Far, Far Away: A Candidate z similar to 12 Galaxy in Early JWST CEERS Imaging

Michaela Hirschmann

We report the discovery of a candidate galaxy with a photo -z of z similar to 12 in the first epoch of the James Webb Space Telescope (JWST) Cosmic Evolution Early Release Science Survey. Following conservative selection criteria, we identify a source with ...

IOP Publishing Ltd2022

Constraining quasar structure using high-frequency microlensing variations and continuum reverberation

Frédéric Courbin, Vivien François Bonvin, Martin Raoul Robert Millon, Hung-Hsu Chan, Georgios Vernardos, Eric Gérard Guy Paic

Gravitational microlensing is a powerful tool for probing the inner structure of strongly lensed quasars and for constraining parameters of the stellar mass function of lens galaxies. This is achieved by analysing microlensing light curves between the mult ...

EDP SCIENCES S A2022

Survey of Gravitationally lensed objects in HSC Imaging (SuGOHI). VIII. New galaxy-scale lenses from the HSC SSP

Hung-Hsu Chan

We conduct a search for galaxy-scale strong gravitational lens systems in Data Release 4 of the Hyper Suprime-Cam Subaru Strategic Program (HSC SSP), consisting of data taken up to the S21A semester. We select 103191 luminous red galaxies from the Baryon O ...

OXFORD UNIV PRESS2022

The completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: N-body mock challenge for galaxy clustering measurements

Cheng Zhao

We develop a series of N-body data challenges, functional to the final analysis of the extended Baryon Oscillation Spectroscopic Survey (eBOSS) Data Release 16 (DR16) galaxy sample. The challenges are primarily based on high-fidelity catalogues constructed ...

OXFORD UNIV PRESS2021

The AGORA High-resolution Galaxy Simulations Comparison Project. III. Cosmological Zoom-in Simulation of a Milky Way-mass Halo

Yves Revaz, Loïc Hausammann

We present a suite of high-resolution cosmological zoom-in simulations to z = 4 of a 10(12) M (circle dot) halo at z = 0, obtained using seven contemporary astrophysical simulation codes (Art-I, Enzo, Ramses, Changa, Gadget-3, Gear, and Gizmo) widely used ...

IOP PUBLISHING LTD2021

The impact of the fiducial cosmology assumption on BAO distance scale measurements

Cheng Zhao

Standard analysis pipelines for measurements of Baryon Acoustic Oscillations (BAO) in galaxy surveys make use of a fiducial cosmological model to guide the data compression required to transform from observed redshifts and angles to the measured angular an ...

OXFORD UNIV PRESS2020

Effective photon mass and (dark) photon conversion in the inhomogeneous Universe

Kyrylo Bondarenko

Photons traveling cosmological distances through the inhomogeneous Universe experience a great variation in their in-medium induced effective mass. Using the EAGLE suite of hydrodynamical simulations, we infer the free electron distribution and thereby the ...

IOP PUBLISHING LTD2020

Precision theoretical methods for large-scale structure of the Universe

Mikhail Ivanov

We develop new analytic methods to accurately describe the formation of cosmic large-scale structure. These methods are based on the path integral formalism and allows one to efficiently address a number of long-standing problems in the field. We describe ...

EPFL2019

Phenotypic redshifts with self-organizing maps: A novel method to characterize redshift distributions of source galaxies for weak lensing

Eduardo Sanchez, Romain Buchs

Wide-field imaging surveys such as the Dark Energy Survey (DES) rely on coarse measurements of spectral energy distributions in a few filters to estimate the redshift distribution of source galaxies. In this regime, sample variance, shot noise, and selecti ...

2019

Pristine dwarf galaxy survey - I. A detailed photometric and spectroscopic study of the very metal-poor Draco II satellite

Pascale Jablonka, Nicolas Lawrence Etienne Longeard, Silvia Martin de Nicolas Agut

We present a detailed study of the faint Milky Way satellite Draco II (Dra II) from deep CFHT/MegaCam broad-band g and i photometry and narrow-band metallicity-sensitive CaliK observations, along with follow-up Keck II/DEIMOS multi-object spectroscopy. For ...

OXFORD UNIV PRESS2018

Tuning adatom mobility and nanoscale segregation by twin formation and polytypism

Anna Fontcuberta i Morral, Gözde Tütüncüoglu, Federico Matteini, Luca Francaviglia

Nanoscale variations in the composition of an AlxGa1−xAs shell around a GaAs nanowire affect the nanowire functionality and can lead to the formation of localized quantum emitters. These composition fluctuations can be the consequence of variations of crys ...

2018

The SDSS-IV extended Baryon Oscillation Spectroscopic Survey: final emission line galaxy target selection

Yi Wang, Jean-Paul Richard Kneib, Anand Stéphane Raichoor, David Schlegel, Timothée Guy Olivier Delubac, Arjun Dey, Claudio Gorgoni

We describe the algorithm used to select the emission line galaxy (ELG) sample at z similar to 0.85 for the extended Baryon Oscillation Spectroscopic Survey of the Sloan Digital Sky Survey IV, using photometric data from the DECam Legacy Survey. Our select ...

Oxford Univ Press2017

Photometric redshifts and clustering of emission line galaxies selected jointly by DES and eBOSS

Yi Zhang, Jean-Paul Richard Kneib, Eduardo Sanchez, Timothée Guy Olivier Delubac

We present the results of the first observations of the emission line galaxies (ELG) of the extended Baryon Oscillation Spectroscopic Survey. From the total 9000 targets, 4600 have been selected from the Dark Energy Survey (DES). In this subsample, the tot ...

Oxford Univ Press2017

Time-sliced perturbation theory for large scale structure I: general formalism

Sergey Sibiryakov, Diego Blas Temino, Mikhail Ivanov

We present a new analytic approach to describe large scale structure formation in the mildly non-linear regime. The central object of the method is the time-dependent probability distribution function generating correlators of the cosmological observables ...

Iop Publishing Ltd2016

The Sdss-Iv Extended Baryon Oscillation Spectroscopic Survey: Overview And Early Data

Jean-Paul Richard Kneib, Cheng Zhao, Anand Stéphane Raichoor, David Schlegel, Timothée Guy Olivier Delubac, Zheng Zheng

In a six-year program started in 2014 July, the Extended Baryon Oscillation Spectroscopic Survey (eBOSS) will conduct novel cosmological observations using the BOSS spectrograph at Apache Point Observatory. These observations will be conducted simultaneous ...

Iop Publishing Ltd2016

On the strong coupling scale in Higgs G-inflation

Higgs G-inflation is an inflation model that takes advantage of a Galileon-like derivative coupling. It is a non-renormalizable operator and is strongly coupled at high energy scales. Perturbative analysis does not have a predictive power any longer there. ...

Elsevier2015