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Thanks to the accurate determination of the baryon density of the universe by the recent cosmic microwave background experiments, updated predictions of the standard model of Big Bang nucleosynthesis now yield the initial abundance of the…

天体物理学 · 物理学 2015-06-24 C. Charbonnel , F. Primas

The cosmological {7Li problem consists in explaining why the primordial Li abundance, as predicted by the standard Big Bang nucleosynthesis theory with constraints from WMAP and Planck, is a factor of 3 larger than the Li abundance measured…

星系天体物理 · 物理学 2021-05-12 Francesca Matteucci , Marta Molero , David S. Aguado , Donatella Romano

The primordial abundances of Deuterium, he4, and li7 are crucial to determination of the baryon density of the Universe in the framework of standard Big Bang nucleosynthesis (BBN). li6 which is only produced in tiny quantities and it is…

Because of the roughly linear correlation between Be/H and Fe/H in low metallicity halo stars, it has been argued that a ``primary'' component in the nucleosynthesis of Be must be present in addition to the ``secondary'' component from…

天体物理学 · 物理学 2009-10-30 Brian D. Fields , Keith A. Olive

Boron abundances in A- and B-type stars may be a successful way to track evolutionary effects in these hot stars. The light elements -- Li, Be, and B -- are tracers of exposure to temperatures more moderate than those in which the H-burning…

天体物理学 · 物理学 2007-05-23 Kim A. Venn , David L. Lambert , Michael Lemke

We examine the Big Bang nucleosynthesis (BBN) process in the presence of small-scale baryon inhomogeneities. Primordial abundance yields for D, He4, Li6, Li7, Be9, and B11 are computed for wide ranges of parameters characterizing the…

天体物理学 · 物理学 2009-11-06 K. Jedamzik , Jan B. Rehm

Prediction of the primordial abundances of elements in the big-bang nucleosynthesis (BBN) is one of the three strong evidences for the big bang model. Precise knowledge of the baryon-to-photon ratio of the Universe from observations of the…

核理论 · 物理学 2019-06-24 Vinay Singh , Joydev Lahiri , Debasis Bhowmick , D. N. Basu

Primordial or big bang nucleosynthesis (BBN) is one of the three historical strong evidences for the big bang model. The recent results by the Planck satellite mission have slightly changed the estimate of the baryonic density compared to…

宇宙学与河外天体物理 · 物理学 2015-06-19 Alain Coc , Jean-Philippe Uzan , Elisabeth Vangioni

I calculate the evolution of Be and B abundances produced by cosmic rays generated by massive stars in the pregalactic phase of the universe. The inputs for calculation, i.e. the star formation rate and the nuclear abundances of cosmic…

天体物理学 · 物理学 2013-03-21 Motohiko Kusakabe

After few minutes the Universe evolved through conditions of temperature and density which permitted the first synthesis of astrophysically interesting abundances of D, 3He, 4He and 7Li. The relic abundances are sensitive probes of the…

天体物理学 · 物理学 2007-08-30 Paolo Molaro

Primordial or Big Bang nucleosynthesis (BBN) is one of the three historical strong evidences for the Big-Bang model together with the expansion of the Universe and the Cosmic Microwave Background radiation (CMB). The recent results by the…

宇宙学与河外天体物理 · 物理学 2013-07-29 Alain Coc , Jean-Philippe Uzan , Elisabeth Vangioni

One of the most important factors in determining the stellar lithium abundance is the effective temperature. In a previous study by the authors, new effective temperatures Teff for sixteen metal-poor halo dwarfs were derived using a local…

太阳与恒星天体物理 · 物理学 2015-05-18 A. Hosford , A. E. Garcia Perez , R. Collet , S. G. Ryan , J. E. Norris , K. A. Olive

We improve Standard Big Bang Nucleosynthesis (SBBN) calculations taking into account new nuclear physics analyses (Descouvemont et al. 2003). Using a Monte-Carlo technique, we calculate the abundances of light nuclei versus the baryon to…

天体物理学 · 物理学 2009-11-10 A. Coc , E. Vangioni-Flam , P. Descouvemont , A. Adahchour , C. Angulo

Using the recent WMAP determination of the baryon-to-photon ratio, 10^{10} \eta = 6.14 to within a few percent, big bang nucleosynthesis (BBN) calculations can make relatively accurate predictions of the abundances of the light element…

天体物理学 · 物理学 2009-09-15 Richard H. Cyburt , Brian D. Fields , Keith A. Olive

We review the Galactic chemical evolution of Li6 and compare these results with recent observational determinations of the lithium isotopic ratio. In particular, we concentrate on so-called standard Galactic cosmic-ray nucleosynthesis in…

天体物理学 · 物理学 2009-10-31 Brian D. Fields , Keith A. Olive

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…

天体物理学 · 物理学 2007-05-23 Gary Steigman

Big-bang nucleosynthesis (BBN) describes the production of the lightest nuclides via a dynamic interplay among the four fundamental forces during the first seconds of cosmic time. We briefly overview the essentials of this physics, and…

宇宙学与河外天体物理 · 物理学 2016-04-13 Richard H. Cyburt , Brian D. Fields , Keith A. Olive , Tsung-Han Yeh

Using a time-dependent Galactic Cosmic Ray flux proportional to the halo Star Formation Rate and including astration and neutrino-induced nucleosynthesis, we have studied the evolution of lithium, beryllium and boron in the halo. Our…

天体物理学 · 物理学 2007-05-23 Andreu Alibes , Ramon Canal

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…

核理论 · 物理学 2024-05-28 Vinay Singh , Debasis Bhowmick , D. N. Basu

We consider the effect on Big Bang Nucleosynthesis (BBN) of new measurements of the $d(p,\gamma){}^3$He cross section by the LUNA Collaboration. These have an important effect on the primordial abundance of D/H which is also sensitive to…

宇宙学与河外天体物理 · 物理学 2021-03-23 Tsung-Han Yeh , Keith A. Olive , Brian D. Fields
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