相关论文: Simultaneous constraints on the number and mass of…
The neutrino energy density of the Universe can be conveniently parametrized in terms of the so-called effective number of neutrinos, N_nu^eff. This parameter enters in several cosmological observables. In particular it is an important…
Model-independent mass limits assess the robustness of current cosmological measurements of the neutrino mass scale. Consistency between high-multipole and low-multiple Cosmic Microwave Background observations measuring such scale further…
The vast majority of extensions of the Standard Model affecting the number of effective relativistic neutrino species ($N_{\rm eff}$) do so additively, namely, they enhance this quantity with some light state contributing to dark radiation.…
It is generally expected that adding light sterile species would increase the effective number of neutrinos, $N_{eff}$. In this paper we discuss a scenario that $N_{eff}$ can actually decrease due to the neutrino oscillation effect if…
We discuss constraints on the effective number of neutrino species Nnu from recent cosmological observations such as CMB, LSS, BBN, including our own analysis which uses the WMAP and the Luminous Red Galaxy power spectrum data. We also…
Although the MiniBooNE experiment has severely restricted the possible existence of light sterile neutrinos, a few anomalies persist in oscillation data, and the possibility of extra light species contributing as a subdominant hot (or warm)…
A range of experimental results point to the existence of a massive neutrino. The recent high precision measurements of the cosmic microwave background and the large scale surveys of galaxies can be used to place an upper bound on this…
We show that a mass-varying neutrino model driven by scalar field dark energy relaxes the existing upper bound on the current neutrino mass to ${\sum m_\nu < 0.72}$ eV. We extend the standard $\Lambda$ cold dark matter model by introducing…
There is a puzzling contradiction: direct observations favor a low-mass density universe, but the only model which fits universe structure over more than three orders of magnitude in distance scale has a mix of hot (neutrino) and cold dark…
We investigate how the properties of dark energy affect the cosmological measurements of neutrino mass and extra relativistic degrees of freedom. We limit ourselves to the most basic extensions of $\Lambda$ cold dark matter (CDM) model,…
Despite direct observations favoring a low mass density, a critical density universe with a neutrino component of dark matter provides the best existing model to explain the observed structure of the universe over more than three orders of…
Using several cosmological observations, i.e. the cosmic microwave background anisotropies (WMAP), the weak gravitational lensing (CFHTLS), the measurements of baryon acoustic oscillations (SDSS+WiggleZ), the most recent observational…
We examine the performance of the six-parameter $\Lambda$CDM model and its extensions in light of recent cosmological observations, with particular focus on neutrino properties inferred from cosmology. Using a broad suite of nine…
The light neutrino masses are at present most stringently constraint via cosmological probes. In particular the Planck collaboration reports $ \sum m_\nu \leq 0.12\,\mathrm{eV}$ at $95\%$ CL within the standard cosmological model. This is…
Recent work on increasing the effective number of neutrino species (Neff) in the early universe has focussed on introducing extra relativistic species (`dark radiation'). We draw attention to another possibility: a new particle of mass less…
We have derived new bounds on the relativistic energy density in the Universe from cosmic microwave background (CMB), large scale structure (LSS), and type Ia supernova (SNI-a) observations. In terms of the effective number of neutrino…
Combining cosmic microwave background (CMB) data from Planck satellite data, Baryon Acoustic Oscillations (BAO) measurements and Type Ia supernovae (SNe Ia) data, we obtain the bounds on total neutrino masses $M_\nu$ with the approximation…
In the presented work we consider the influence of a hypothetical sterile neutrino (with eV-scale mass) on the determination of cosmological parameters. If it is detected, it will be necessary to include it into the $\Lambda \rm CDM$ model…
We investigate the way how the total mass sum of neutrinos can be constrained from the neutrinoless double beta decay and cosmological probes with cosmic microwave background (WMAP 3-year results), large scale structures including 2dFGRS…
In this thesis, I describe a number of recent important developments in neutrino cosmology on three fronts. Firstly, focusing on Large-Scale Structure (LSS) data, I will show that current cosmological probes contain a wealth of information…