Related papers: Using BBN in cosmological parameter extraction fro…
Primordial or big bang nucleosynthesis (BBN) is one of the three historical strong evidences for the big bang model. Standard BBN is now a parameter free theory, since the baryonic density of the Universe has been deduced with an…
Primordial nucleosynthesis provides a probe of the Universe during its early evolution. Given the progress exploring the constituents, structure, and recent evolution of the Universe, it is timely to review the status of Big Bang…
The importance of the Big Bang Nucleosynthesis (BBN) as a unique tool for studying neutrino properties is discussed, and the recent steps towards a self-consistent and robust handling of the weak reaction decoupling from the thermal bath as…
The lecture is devoted to the comparison of a few models of cosmic recombination kinetics with recent CMB anisotropy data and to corresponding predictions for the upcoming PLANCK mission. The influence of additional sources of ionized…
One of the three testaments in favor of the big bang theory is the prediction of the primordial elemental abundances in the big-bang nucleosynthesis (BBN). The Standard BBN is a parameter-free theory due to the precise knowledge of the…
We re-examine the systematic errors in the determination of the primordial helium abundance, $Y_{\rm P}$. We find that the systematics are significantly larger than the statistical errors. The uncertainty in (the determination of) $Y_{\rm…
Data from Type Ia supernovae, along with X-ray cluster estimates of the universal baryon fraction and Big Bang Nucleosynthesis (BBN) determinations of the baryon-to-photon ratio, are used to provide estimates of several global cosmological…
In this work, we investigate the viability of some cosmological models derived from generalized horizon entropies, using Big Bang Nucleosynthesis (BBN) constraints. By analyzing the deviations in the expansion rate, we derive bounds on the…
The precision measurement of the primordial helium abundance $Y_p$ is a powerful probe of the early Universe. The most common way to determine $Y_p$ is analyses of observations of metal-poor \HII regions found in blue compact dwarf…
We consider heavy sterile neutrinos $\nu_s$, with mass in the range 10 MeV $\lesssim m_s \lesssim m_{\pi} \sim 135$ MeV, thermally produced in the early universe and freezing out after the QCD phase transition. The existence of these…
The primordial abundance of deuterium produced during Big Bang Nucleosynthesis (BBN) depends sensitively on the universal ratio of baryons to photons, an important cosmological parameter probed independently by the Cosmic Microwave…
Primordial neutrino-antineutrino asymmetries can be constrained through big-bang nucleosynthesis (BBN) relic abundances and cosmic microwave background (CMB) anisotropies, both observables being sensitive to neutrino properties. The latter…
The primordial abundances of deuterium, helium-3, helium-4, and lithium-7 probe the baryon density of the Universe only a few minutes after the Big Bang. Of these relics from the early Universe, deuterium is the baryometer of choice. After…
After reviewing the main mechanisms by which cosmological measurements constrain the sum of neutrino masses, I give the current reached upper limits, emphasizing the level of model-dependence. A large improvement is to be expected with…
Effects of light millicharged dark matter particles on primordial nucleosynthesis are considered. It is shown that if the mass of such particles is much smaller than the electron mass, they lead to strong overproduction of Helium-4. An…
The existence of the cosmic neutrino background is a fascinating prediction of the hot big bang model. These neutrinos were a dominant component of the energy density in the early universe and, therefore, played an important role in the…
Big bang nucleosynthesis has long provided the primary determination of the cosmic baryon density $\omb h^2$, or equivalently the baryon-to-photon ratio, \eta. Recently, data on CMB anisotropies have become increasingly sensitive to \eta.…
We present cosmological constraints on deviations of Newton's constant at large scales, analyzing latest cosmic microwave background (CMB) anisotropies and primordial abundances of light elements synthesized by big bang nucleosynthesis…
One of the main obstacles for extracting the Cosmic Microwave Background (CMB) from mm/submm observations is the pollution from the main Galactic components: synchrotron, free-free and thermal dust emission. The feasibility of using simple…
We introduce a new statistical method to estimate the primordial helium abundance, Y_p from observed abundances in a sample of galaxies which have experienced stellar helium enrichment. Rather than using linear regression on metal abundance…