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Julien Lesgourgues

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Related publications (71)

Planck 2013 results. XII. Diffuse component separation

Julien Lesgourgues, Fabio Finelli, Xin Chen

Planck has produced detailed all-sky observations over nine frequency bands between 30 and 857 GHz. These observations allow robust reconstruction of the primordial cosmic microwave background (CMB) temperature fluctuations over nearly the full sky, as wel ...

Edp Sciences S A2014

Constraints on primordial non-Gaussianity

Julien Lesgourgues, Fabio Finelli

The Planck nominal mission cosmic microwave background (CMB) maps yield unprecedented constraints on primordial non-Gaussianity (NG). Using three optimal bispectrum estimators, separable template-fitting (KSW), binned, and modal, we obtain consistent value ...

Edp Sciences S A2014

Planck 2013 results. XXIX. The Planck catalogue of Sunyaev-Zeldovich sources

Julien Lesgourgues, Fabio Finelli, Xin Chen

We describe the all-sky Planck catalogue of clusters and cluster candidates derived from Sunyaev-Zeldovich (SZ) effect detections using the first 15.5 months of Planck satellite observations. The catalogue contains 1227 entries, making it over six times th ...

Edp Sciences S A2014

Planck 2013 results. XXVIII. The Planck Catalogue of Compact Sources

Julien Lesgourgues, Fabio Finelli, Benjamin Andreas Walter, Xin Chen

The Planck Catalogue of Compact Sources (PCCS) is the catalogue of sources detected in the first 15 months of Planck operations, the "nominal" mission. It consists of nine single-frequency catalogues of compact sources, both Galactic and extragalactic, det ...

Edp Sciences S A2014

Planck 2013 results. XVIII. The gravitational lensing-infrared background correlation

Julien Lesgourgues, Fabio Finelli

The multi-frequency capability of the Planck satellite provides information both on the integrated history of star formation (via the cosmic infrared background, or CIB) and on the distribution of dark matter (via the lensing effect on the cosmic microwave ...

Edp Sciences S A2014

Planck 2013 results. XIII. Galactic CO emission

Julien Lesgourgues, Fabio Finelli, Xin Chen

Rotational transition lines of CO play a major role in molecular radio astronomy as a mass tracer and in particular in the study of star formation and Galactic structure. Although a wealth of data exists for the Galactic plane and some well-known molecular ...

Edp Sciences S A2014

Constraining dark matter-neutrino interactions using the CMB and large-scale structure

Julien Lesgourgues

We present a new study on the elastic scattering cross section of dark matter (DM) and neutrinos using the latest cosmological data from Planck and large-scale structure experiments. We find that the strongest constraints are set by the Lyman-a forest, giv ...

Iop Publishing Ltd2014

Cosmological parameter estimation with large scale structure observations

Ruth Durrer, Julien Lesgourgues

We estimate the sensitivity of future galaxy surveys to cosmological parameters, using the redshift dependent angular power spectra of galaxy number counts, C-l(z(1), z(2)), calculated with all relativistic corrections at first order in perturbation theory ...

Iop Publishing Ltd2014

Planck 2013 results. XVI. Cosmological parameters

Julien Lesgourgues, Fabio Finelli, Jan Hamann, Xin Chen

This paper presents the first cosmological results based on Planck measurements of the cosmic microwave background (CMB) temperature and lensing-potential power spectra. We find that the Planck spectra at high multipoles (l greater than or similar to 40) a ...

Edp Sciences S A2014

Planck 2013 results. II. Low Frequency Instrument data processing

Julien Lesgourgues, Fabio Finelli, Xin Chen

We describe the data processing pipeline of the Planck Low Frequency Instrument (LFI) data processing centre (DPC) to create and characterize full-sky maps based on the first 15.5 months of operations at 30, 44, and 70 GHz. In particular, we discuss the va ...

Edp Sciences S A2014

CMB power spectra and likelihood

Julien Lesgourgues, Fabio Finelli

This paper presents the Planck 2013 likelihood, a complete statistical description of the two-point correlation function of the CMB temperature fluctuations that accounts for all known relevant uncertainties, both instrumental and astrophysical in nature. ...

Edp Sciences S A2014

Planck 2013 results. IX. HFI spectral response

Julien Lesgourgues, Fabio Finelli, Xin Chen

The Planck High Frequency Instrument (HFI) spectral response was determined through a series of ground based tests conducted with the HFI focal plane in a cryogenic environment prior to launch. The main goal of the spectral transmission tests was to measur ...

Edp Sciences S A2014

The effective gravitational decoupling between dark matter and the CMB

Luc Voruz, Julien Lesgourgues

We present a detailed and self-contained analytical derivation of the evolution of sub-horizon cosmological perturbations before decoupling, based on previous work by S. Weinberg. These solutions are valid in the minimal Lambda CDM scenario, to first order ...

Iop Publishing Ltd2014

Planck 2013 results. XXI. Power spectrum and high-order statistics of the Planck all-sky Compton parameter map

Julien Lesgourgues, Fabio Finelli

We have constructed the first all-sky map of the thermal Sunyaev-Zeldovich (tSZ) effect by applying specifically tailored component separation algorithms to the 100 to 857 GHz frequency channel maps from the Planck survey. This map shows an obvious galaxy ...

Edp Sciences S A2014

Planck 2013 results. XX. Cosmology from Sunyaev-Zeldovich cluster counts

Julien Lesgourgues, Fabio Finelli

We present constraints on cosmological parameters using number counts as a function of redshift for a sub-sample of 189 galaxy clusters from the Planck SZ (PSZ) catalogue. The PSZ is selected through the signature of the Sunyaev-Zeldovich (SZ) effect, and ...

Edp Sciences S A2014

Planck 2013 results. XXX. Cosmic infrared background measurements and implications for star formation

Julien Lesgourgues, Fabio Finelli, Xin Chen

We present new measurements of cosmic infrared background (CIB) anisotropies using Planck. Combining HFI data with IRAS, the angular auto-and cross-frequency power spectrum is measured from 143 to 3000 GHz, and the auto-bispectrum from 217 to 545 GHz. The ...

Edp Sciences S A2014

Structure formation with massive neutrinos: going beyond linear theory

Julien Lesgourgues, Diego Blas Temino

We compute non-linear corrections to the matter power spectrum taking the time-and scale-dependent free-streaming length of neutrinos into account. We adopt a hybrid scheme that matches the full Boltzmann hierarchy to an effective two-fluid description at ...

Iop Publishing Ltd2014

Strongest model-independent bound on the lifetime of Dark Matter

Julien Lesgourgues, Benjamin Audren

Dark Matter is essential for structured formation in the late Universe so it must be stable on cosmological time scales. But how stable exactly? Only assuming decays into relativistic on particles, we report an otherwise model independent bound on the life ...

Iop Publishing Ltd2014

Planck 2013 results. VII. HFI time response and beams

Julien Lesgourgues, Fabio Finelli

This paper characterizes the effective beams, the effective beam window functions and the associated errors for the Planck High Frequency Instrument (HFI) detectors. The effective beam is the angular response including the effect of the optics, detectors, ...

Edp Sciences S A2014

Planck 2013 results. XXV. Searches for cosmic strings and other topological defects

Julien Lesgourgues, Fabio Finelli, Jason Douglas McEwen

Planck data have been used to provide stringent new constraints on cosmic strings and other defects. We describe forecasts of the CMB power spectrum induced by cosmic strings, calculating these from network models and simulations using line-of-sight Boltzm ...

Edp Sciences S A2014

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