Search Publications
Measuring growth index in a universe with massive neutrinos: A revisit of the general relativity test with the latest observations
Zhang, Jing-Fei; Zhang, Xin; Zhao, Ming-Ming
We make a consistency test for the general relativity (GR) through measuring the growth index γ in a universe with massive (sterile/active) neutrinos. We employ the redshift space distortion measurements to do the analysis. To constrain other cosmological parameters, we also use other cosmological measurements, including the Planck 2015 cosmic mic…
A novel approach to quantifying the sensitivity of current and future cosmological datasets to the neutrino mass ordering through Bayesian hierarchical modeling
Mena, Olga; Gerbino, Martina; Lattanzi, Massimiliano +1 more
We present a novel approach to derive constraints on neutrino masses, as well as on other cosmological parameters, from cosmological data, while taking into account our ignorance of the neutrino mass ordering. We derive constraints from a combination of current as well as future cosmological datasets on the total neutrino mass Mν and on…
A combined view of sterile-neutrino constraints from CMB and neutrino oscillation measurements
Bridle, Sarah; Elvin-Poole, Jack; Evans, Justin +3 more
We perform a comparative analysis of constraints on sterile neutrinos from the Planck experiment and from current and future neutrino oscillation experiments (MINOS, IceCube, SBN). For the first time, we express joint constraints on Neff and meffsterile from the CMB in the Δm2, sin2 2 θ para…
Asymmetric Dark Matter in the shear-dominated universe
Iminniyaz, Hoernisa
We explore the relic abundance of asymmetric Dark Matter in shear-dominated universe in which it is assumed the universe is expanded anisotropically. The modified expansion rate leaves its imprint on the relic density of asymmetric Dark Matter particles if the asymmetric Dark Matter particles are decoupled in shear dominated era. We found the reli…
Reconciling Planck with the local value of H0 in extended parameter space
Di Valentino, Eleonora; Melchiorri, Alessandro; Silk, Joseph
The recent determination of the local value of the Hubble constant by Riess et al., 2016 (hereafter R16) is now 3.3 sigma higher than the value derived from the most recent CMB anisotropy data provided by the Planck satellite in a ΛCDM model. Here we perform a combined analysis of the Planck and R16 results in an extended parameter space, varying …
Cosmological axion and neutrino mass constraints from Planck 2015 temperature and polarization data
Di Valentino, Eleonora; Melchiorri, Alessandro; Mena, Olga +3 more
Axions currently provide the most compelling solution to the strong CP problem. These particles may be copiously produced in the early universe, including via thermal processes. Therefore, relic axions constitute a hot dark matter component and their masses are strongly degenerate with those of the three active neutrinos, as they leave identical s…
New constraints on primordial gravitational waves from Planck 2015
Melchiorri, Alessandro; Pagano, Luca; Salvati, Laura
We show that the new precise measurements of Cosmic Microwave Background (CMB) temperature and polarization anisotropies made by the Planck satellite significantly improves previous constraints on the cosmic gravitational waves background (CGWB) at frequencies f >10-15 Hz. On scales smaller than the horizon at the time of decoupling,…
CMB constraint on dark matter annihilation after Planck 2015
Nakayama, Kazunori; Kawasaki, Masahiro; Sekiguchi, Toyokazu
We update the constraint on the dark matter annihilation cross section by using the recent measurements of the CMB anisotropy by the Planck satellite. We fully calculate the cascade of dark matter annihilation products and their effects on ionization, heating and excitation of the hydrogen, hence do not rely on any assumption on the energy fractio…
Galaxy clustering, CMB and supernova data constraints on ϕCDM model with massive neutrinos
Xu, Lixin; Chen, Yun
We investigate a scalar field dark energy model (i.e., ϕCDM model) with massive neutrinos, where the scalar field possesses an inverse power-law potential, i.e., V (ϕ) ∝ϕ-α (α > 0). We find that the sum of neutrino masses Σmν has significant impacts on the CMB temperature power spectrum and on the matter power spectrum. In…
Direct search for features in the primordial bispectrum
Appleby, Stephen; Hazra, Dhiraj Kumar; Gong, Jinn-Ouk +2 more
We study features in the bispectrum of the primordial curvature perturbation correlated with the reconstructed primordial power spectrum from the observed cosmic microwave background temperature data. We first show how the bispectrum can be completely specified in terms of the power spectrum and its first two derivatives, valid for any configurati…