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Related papers: New results in primordial nucleosynthesis

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A massive long-lived tau neutrino in the MeV regime modifies the primordial light-element abundances predicted by big-bang nucleosynthesis (BBN) calculations. This effect has been used to derive limits on the tau neutrino mass. Because…

Astrophysics · Physics 2011-05-23 J. B. Rehm , G. G. Raffelt , A. Weiss

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…

Nuclear Theory · Physics 2024-05-28 Vinay Singh , Debasis Bhowmick , D. N. Basu

We present an up-to-date review of Big Bang Nucleosynthesis (BBN). We discuss the main improvements which have been achieved in the past two decades on the overall theoretical framework, summarize the impact of new experimental results on…

Astrophysics · Physics 2009-04-21 F. Iocco , G. Mangano , G. Miele , O. Pisanti , P. D. Serpico

We put bounds on the variation of the value of the fine structure constant $\alpha$, at the time of Big Bang nucleosynthesis. We study carefully all light elements up to $^7$Li. We correct a previous upper limit on $|\Delta \alpha /…

Astrophysics · Physics 2009-10-31 L. Bergstrom , S. Iguri , H. Rubinstein

We analyze the effect of variation of fundamental couplings and mass scales on primordial nucleosynthesis in a systematic way. The first step establishes the response of primordial element abundances to the variation of a large number of…

Astrophysics · Physics 2008-12-18 Thomas Dent , Steffen Stern , Christof Wetterich

An introductory review of the early evolution of the Universe relevant to the primordial synthesis of the light nuclides deuterium, helium-3, helium-4 and lithium-7. The predictions of the element abundances in the "standard", hot, big bang…

Astrophysics · Physics 2009-10-31 Gary Steigman

We assess the effects on Big Bang Nucleosynthesis (BBN) of lepton number generation in the early universe resulting from the two-doublet four-neutrino mass/mixing scheme. It has been argued that this neutrino mass/mixing arrangement gives…

Astrophysics · Physics 2009-10-31 Kevork Abazajian , George M. Fuller , Xiangdong Shi

Big-bang nucleosynthesis (BBN) theory, together with the precise WMAP cosmic baryon density, makes tight predictions for the abundances of the lightest elements. Deuterium and 4He measurements agree well with expectations, but 7Li…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-19 Brian D. Fields

We present two new primary mechanisms for the synthesis of the rare nucleus 9Be, both triggered by nu-induced production of 3H followed by 4He(3H,gamma)7Li in the He shells of core-collapse supernovae. For progenitors of ~8M_sun,…

Solar and Stellar Astrophysics · Physics 2015-06-12 P. Banerjee , Y. -Z. Qian , W. C. Haxton , A. Heger

The products of primordial nucleosynthesis and the cosmic microwave background (CMB) photons are relics from the early evolution of the Universe whose observations probe the standard model of cosmology and provide windows on new physics…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Gary Steigman

I review measurements of the most important reactions involved in the creation and destruction of Li and Be during big bang nucleosynthesis (BBN) as well as their uncertainties and the relative contributions they make to the uncertainty in…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-14 Barry Davids

We revisit the upper limits on the abundance of unstable massive relic particles provided by the success of Big-Bang Nucleosynthesis calculations. We use the cosmic microwave background data to constrain the baryon-to-photon ratio, and…

Astrophysics · Physics 2009-09-11 Richard H. Cyburt , John Ellis , Brian D. Fields , Keith A. Olive

We study the dependence of the primordial nuclear abundances as a function of the electromagnetic fine-structure constant $\alpha$, keeping all other fundamental constants fixed. We update the leading nuclear reaction rates, in particular…

High Energy Physics - Theory · Physics 2023-05-26 Ulf-G. Meißner , Bernard Ch. Metsch , Helen Meyer

Primordial nucleosynthesis is one of the three historical evidences for the big bang model, together with the expansion of the universe and the cosmic microwave background. Now that the number of neutrino families and the baryonic densities…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-07 Cyril Pitrou , Alain Coc , Jean-Philippe Uzan , Elisabeth Vangioni

Within the first 20 minutes of the evolution of the hot, dense, early Universe, astrophysically interesting abundances of deuterium, helium-3, helium-4, and lithium-7 were synthesized by the cosmic nuclear reactor. The primordial abundances…

Astrophysics · Physics 2007-05-23 Gary Steigman

Primordial nucleosynthesis is inevitable during the early evolution of an expanding universe filled with radiation and matter (baryons). However, the precise abundance yields depend sensitively on the baryon density, the radiation content…

Astrophysics · Physics 2007-05-23 Gary Steigman

Limits can be placed on nonstandard neutrino physics when big bang nucleosynthesis (BBN) calculations employing standard neutrino physics agree with the observationally inferred primordial abundances of deuterium (D), $^3$He, $^4$He, and…

Astrophysics · Physics 2007-05-23 Christian Y. Cardall , George M. Fuller

During its early evolution the Universe provided a laboratory to probe fundamental physics at high energies. Relics from those early epochs, such as the light elements synthesized during primordial nucleosynthesis when the Universe was only…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-22 Gary Steigman

We verified the validity of the empirical method to derive the 4He abundance used in our previous papers by applying it to CLOUDY (v13.01) models. Using newly published HeI emissivities, for which we present convenient fits as well as the…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-03 Y. I. Izotov , G. Stasinska , N. G. Guseva

Catalysis of nuclear reactions by metastable charged particles X^- opens the possibility for primordial production of elements with A>7. We calculate the abundance of ^9Be, where synthesis is mediated by the formation of (^8Be X^-) bound…

High Energy Physics - Phenomenology · Physics 2007-12-06 Maxim Pospelov
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