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Publications associées (29)

On the dark radiation problem in the axiverse

Anna Tokareva

String scenarios generically predict that we live in a so called axiverse: the Universe with about a hundred of light axion species which are decoupled from the Standard Model particles. However, the axions can couple to the inflaton which leads to their p ...

Iop Publishing Ltd2017

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 clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: single-probe measurements from CMASS anisotropic galaxy clustering

Jean-Paul Richard Kneib, David Schlegel, Yuting Wang

With the largest spectroscopic galaxy survey volume drawn from the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS), we can extract cosmological constraints from the measurements of redshift and geometric distortions at quasi-linear scales (e.g. abo ...

Oxford Univ Press2016

Hypermagnetic fields and baryon asymmetry from pseudoscalar inflation

Eray Sabancilar

We show that maximally helical hypermagnetic fields produced during pseudoscalar inflation can generate the observed baryon asymmetry of the Universe via the B + L anomaly in the Standard Model. We find that most of the parameter space of pseudoscalar infl ...

American Physical Society2015

Fast and accurate CMB computations in non-flat FLRW universes

Julien Lesgourgues

We present a new method for calculating CMB anisotropies in a non-flat Friedmann universe, relying on a very stable algorithm for the calculation of hyperspherical Bessel functions, that can be pushed to arbitrary precision levels. We also introduce a new ...

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. XXIII. Isotropy and statistics of the CMB

Julien Lesgourgues, Jason Douglas McEwen, Ji Hyun Kim, Fabio Finelli

The two fundamental assumptions of the standard cosmological model - that the initial fluctuations are statistically isotropic and Gaussian - are rigorously tested using maps of the cosmic microwave background (CMB) anisotropy from the Planck satellite. Th ...

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

Optimal polarisation equations in FLRW universes

Julien Lesgourgues

This paper presents the linearised Boltzmann equation for photons for scalar, vector and tensor perturbations in flat, open and closed FLRW cosmologies. We show that E- and B-mode polarisation for all types can be computed using only a single hierarchy. Th ...

Iop Publishing Ltd2013

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