Publications by Julien Lesgourgues

Euclid: Validation of the MontePython forecasting tools

Slobodan Ilic, Georges Meylan, Frédéric Courbin, Julien Lesgourgues, Richard Massey, Maurizio Martinelli, Jean-Luc Starck, Yi Wang

Context. The Euclid mission of the European Space Agency will perform a survey of weak lensing cosmic shear and galaxy clustering in order to constrain cosmological models and fundamental physics. Aims. We expand and adjust the mock Euclid likelihoods of t ...

Edp Sciences S A2024

Cosmology intertwined: A review of the particle physics, astrophysics, and cosmology associated with the cosmological tensions and anomalies

Frédéric Courbin, Julien Lesgourgues, Fabio Finelli, Florian Niedermann, Mikhail Ivanov, Emre Ozulker, Melissa Joseph, Suresh Kumar, Richard Irving Anderson, Hsin-Yu Chen, Jie Wang, Adriano Agnello

The standard Lambda Cold Dark Matter (Lambda CDM) cosmological model provides a good description of a wide range of astrophysical and cosmological data. However, there are a few big open questions that make the standard model look like an approximation to ...

ELSEVIER2022

REVIEW OF PARTICLE PHYSICS Particle Data Group

Kai Oliver Arras, Christophe Bauer, Olivier Schneider, Riddhiman Sarkar, Julien Lesgourgues, Florian Patrick Marie Daniel De la Barre De Nanteuil, Greig Alan Cowan, Varun Sharma, Frank Zimmermann, Lorena Gonçalves de Alcântara e Freitas Krikler, Vladimir Petrov

The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 2,873 new measurements from 758 papers, we list, evaluate, and average measured properties of gauge bosons and the recently discovered Higgs boson, lepton ...

American Physical Society2018

A White Paper on keV sterile neutrino Dark Matter

Laurent Gastaldo, Igor Tkachev, Alexey Boyarsky, Oleg Ruchayskiy, Julien Lesgourgues, Marco Drewes, Antoine Pierre Emmanuel Alexis Merle, Jan Hamann, Jonathan Leon Wolf

We present a comprehensive review of keV-scale sterile neutrino Dark Matter, collecting views and insights from all disciplines involved - cosmology, astrophysics, nuclear, and particle physics - in each case viewed from both theoretical and experimental/o ...

Iop Publishing Ltd2017

Planck intermediate results XXX. The angular power spectrum of polarized dust emission at intermediate and high Galactic latitudes

Julien Lesgourgues, Fabio Finelli

The polarized thermal emission from diffuse Galactic dust is the main foreground present in measurements of the polarization of the cosmic microwave background (CMB) at frequencies above 100 GHz. In this paper we exploit the uniqueness of the Planck HFI po ...

EDP Sciences2016

Constraint on neutrino masses from SDSS-III/BOSS Ly alpha forest and other cosmological probes

Julien Lesgourgues, Arnaud Borde

We present constraints on the parameters of the ACDM cosmological model in the presence of massive neutrinos, using the one-dimensional Ly alpha forest power spectrum obtained with the Baryon Oscillation Spectroscopic Survey (BOSS) of the Sloan Digital Sky ...

Iop Publishing Ltd2015

Robustness of cosmic neutrino background detection in the cosmic microwave background

Julien Lesgourgues, Benjamin Audren

The existence of a cosmic neutrino background can be probed indirectly by CMB experiments, not only by measuring the background density of radiation in the universe, but also by searching for the typical signatures of the fluctuations of free-streaming spe ...

Iop Publishing Ltd2015

Neutrino masses and cosmology with Lyman-alpha forest power spectrum

Julien Lesgourgues, Arnaud Borde

We present constraints on neutrino masses, the primordial fluctuation spectrum from inflation, and other parameters of the ACDM model, using the one-dimensional Ly alpha-forest power spectrum measured by [1] from the Baryon Oscillation Spectroscopic Survey ...

Iop Publishing Ltd2015

Planck intermediate results XXIV. Constraints on variations in fundamental constants

Julien Lesgourgues, Fabio Finelli

Any variation in the fundamental physical constants, more particularly in the fine structure constant, a, or in the mass of the electron, me, affects the recombination history of the Universe and cause an imprint on the cosmic microwave background angular ...

EDP Sciences2015

Cosmological constraints on deviations from Lorentz invariance in gravity and dark matter

Sergey Sibiryakov, Julien Lesgourgues, Diego Blas Temino, Benjamin Audren, Mikhail Ivanov

We consider a scenario where local Lorentz invariance is violated by the existence of a preferred time direction at every space-time point. This scenario can arise in the context of quantum gravity and its description at low energies contains a unit time-l ...

Iop Publishing Ltd2015

Planck 2013 results. XXXII. The updated Planck catalogue of Sunyaev-Zeldovich sources

Julien Lesgourgues, Fabio Finelli, Xin Chen

We update the all-sky Planck catalogue of 1227 clusters and cluster candidates (PSZ1) published in March 2013, derived from detections of the Sunyaev-Zeldovich (SZ) effect using the first 15.5 months of Planck satellite observations. As an addendum, we del ...

Edp Sciences S A2015

Planck 2013 results. VIII. HFI photometric calibration and mapmaking

Julien Lesgourgues, Fabio Finelli, Xin Chen

This paper describes the methods used to produce photometrically calibrated maps from the Planck High Frequency Instrument (HFI) cleaned, time-ordered information. HFI observes the sky over a broad range of frequencies, from 100 to 857 GHz. To obtain the b ...

Edp Sciences S A2014

Planck 2013 results. XI. All-sky model of thermal dust emission

Julien Lesgourgues, Fabio Finelli

This paper presents an all-sky model of dust emission from the Planck 353, 545, and 857 GHz, and IRAS 100 mu m data. Using a modified blackbody fit to the data we present all-sky maps of the dust optical depth, temperature, and spectral index over the 353- ...

Edp Sciences S A2014

Neutrino cosmology and Planck

Julien Lesgourgues

Relic neutrinos play an important role in the evolution of the Universe, modifying some of the cosmological observables. We summarize the main aspects of cosmological neutrinos and describe how the precision of present cosmological data can be used to lear ...

Iop Publishing Ltd2014

Planck 2013 results. XIX. The integrated Sachs-Wolfe effect

Slobodan Ilic, Julien Lesgourgues, Fabio Finelli

Based on cosmic microwave background (CMB) maps from the 2013 Planck Mission data release, this paper presents the detection of the integrated Sachs-Wolfe (ISW) effect, that is, the correlation between the CMB and large-scale evolving gravitational potenti ...

Edp Sciences S A2014

Planck 2013 results. XXXI. Consistency of the Planck data

Julien Lesgourgues, Fabio Finelli

The Planck design and scanning strategy provide many levels of redundancy that can be exploited to provide tests of internal consistency. One of the most important is the comparison of the 70 GHz (amplifier) and 100 GHz (bolometer) channels. Based on diffe ...

Edp Sciences S A2014

Zodiacal emission

Julien Lesgourgues, Fabio Finelli, Xin Chen

The Planck satellite provides a set of all-sky maps at nine frequencies from 30 GHz to 857 GHz. Planets, minor bodies, and di ff use interplanetary dust emission (IPD) are all observed. The IPD can be separated from Galactic and other emissions because Pla ...

Edp Sciences S A2014

LFI systematic uncertainties

Julien Lesgourgues, Fabio Finelli

We present the current estimate of instrumental and systematic effect uncertainties for the Planck-Low Frequency Instrument relevant to the first release of the Planck cosmological results. We give an overview of the main effects and of the tools and metho ...

Edp Sciences S A2014

Planck 2013 results. XXVI. Background geometry and topology of the Universe

Julien Lesgourgues, Fabio Finelli, Jason Douglas McEwen

The new cosmic microwave background (CMB) temperature maps from Planck provide the highest-quality full-sky view of the surface of last scattering available to date. This allows us to detect possible departures from the standard model of a globally homogen ...

Edp Sciences S A2014

HFI energetic particle effects: characterization, removal, and simulation

Julien Lesgourgues, Fabio Finelli

We describe the detection, interpretation, and removal of the signal resulting from interactions of high energy particles with the Planck High Frequency Instrument (HFI). There are two types of interactions: heating of the 0.1 K bolometer plate; and glitch ...

Edp Sciences S A2014