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Related papers: The Baryon Budget from BBN and the CBR

200 papers

The cosmic baryon budget is revisited using modern observations that have become available since our first publication. I also present an estimate for the heavy element abundance. An increased accuracy in the accounting of the baryon budget…

Astrophysics · Physics 2007-05-23 Masataka Fukugita

We discuss the present bounds on the relativistic energy density in the Universe parameterized in terms of the effective number of neutrinos N using the most recent cosmological data on Cosmic Microwave Background (CMB) temperature…

Astrophysics · Physics 2010-10-27 Gianpiero Mangano , Alessandro Melchiorri , Olga Mena , Gennaro Miele , Anze Slosar

We derive constraints on the time variation of the Higgs vacuum expectation value $<\phi>$ through the effects on Big Bang nucleosynthesis (BBN) and the cosmic microwave background (CMB). In the former case, we include the…

Astrophysics · Physics 2009-11-07 Jerry Jaiyul Yoo , Robert J. Scherrer

We extend the model-independent likelihood analysis of big bang nucleosynthesis (BBN) based on He4 and Li7 to allow for numbers of degrees of freedom which differ from the standard model value characterized by $N_\nu = 3$. We use the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Keith A. Olive , David Thomas

A host of dark energy models and non-standard cosmologies predict an enhanced Hubble rate in the early Universe: perfectly viable models, which satisfy Big Bang Nucleosynthesis (BBN), cosmic microwave background and general relativity…

High Energy Physics - Phenomenology · Physics 2009-11-11 M. Schelke , R. Catena , N. Fornengo , A. Masiero , M. Pietroni

The concordance of standard big bang nucleosynthesis theory and the related observations of the light element isotopes (including some new higher \he4 abundances) will be reviewed. Implications of BBN on chemical evolution, dark matter and…

Astrophysics · Physics 2009-09-15 Keith A. Olive

Big Bang nucleosynthesis (BBN) theory predicts the abundances of the light elements D, $^3$He, $^4$He and $^7$Li produced in the early universe. The primordial abundances of D and $^4$He inferred from observational data are in good…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-17 S. Q. Hou , J. J. He , A. Parikh , D. Kahl , C. A. Bertulani , T. Kajino , G. J. Mathews , G. Zhao

The baryon-antibaryon asymmetry (excess of matter over antimatter in our Universe), indicated by observational data from the Cosmic Microwave Background anisotropies, predictions of primordial Nucleosynthesis, and the absence of intense…

General Relativity and Quantum Cosmology · Physics 2020-10-13 P. C. M. Delgado , M. B. Jesus , N. Pinto-Neto , T. Mourão , G. S. Vicente

The theoretical predictions of big bang nucleosynthesis (BBN) are dominated by uncertainties in the input nuclear reaction cross sections. In this paper, we examine the impact on BBN of the recent compilation of nuclear data and…

Astrophysics · Physics 2009-09-15 Richard H. Cyburt , Brian D. Fields , Keith A. Olive

We report the results of a new accurate evaluation of light nuclei yields in primordial nucleosynthesis. All radiative effects, finite nucleon mass, thermal and plasma corrections are included in the proton to neutron conversion rates. The…

Astrophysics · Physics 2008-11-26 S. Esposito , G. Mangano , G. Miele , O. Pisanti

The discovery and confirmation that some nuclides were formed soon after the Big Bang is one of the strongest arguments in favour of the Hot Big Bang theory. The process of combining protons and neutrons in a hot, expanding universe is…

Nuclear Theory · Physics 2024-10-03 D. N. Basu

Big-Bang cosmology and ideas for possible physics beyond the Standard Model of particle physics are introduced. The density budget of the Universe is audited, and the issues involved in calculating the baryon density from microphysics are…

Astrophysics · Physics 2009-09-11 John Ellis

We show that Big Bang Nucleosynthesis (BBN) significantly constrains axion-like dark matter. The axion acts like an oscillating QCD $\theta$ angle that redshifts in the early universe, increasing the neutron-proton mass difference at…

High Energy Physics - Phenomenology · Physics 2015-06-18 Kfir Blum , Raffaele Tito D'Agnolo , Mariangela Lisanti , Benjamin R. Safdi

To constrain the universe before recombination (380000 years after the Big Bang), we mostly rely on the measurements of the primordial abundances that indicate the first insight into the thermal history of the universe. The first production…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-30 Tahani Makki , Mounib El Eid , Grant Mathews

The measurement of the cosmic microwave background has strongly constrained the cosmological parameters of the Universe. When the measured density of baryons (ordinary matter) is combined with standard Big Bang nucleosynthesis calculations,…

Precision on primordial abundances, deduced from observations, have now reached the percent level for 4He and deuterium. Precision on big bang nucleosynthesis (BBN) predictions should, hence, reach the same level. The uncertainty on the 4He…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-27 Cyril Pitrou , Alain Coc , Jean-Philippe Uzan , Elisabeth Vangioni

We test different Big Bang Nucleosynthesis scenarios using the recent results on the Cosmic Microwave Background Anisotropies provided by the BOOMERanG and MAXIMA-1 experiments versus the observed abundances of 4He, D and 7Li. The…

Astrophysics · Physics 2009-10-31 S. Esposito , G. Mangano , A. Melchiorri , G. Miele , O. Pisanti

We use Big Bang Nucleosynthesis (BBN) data in order to impose constraints on the exponent of Barrow entropy. The latter is an extended entropy relation arising from the incorporation of quantum-gravitational effects on the black-hole…

General Relativity and Quantum Cosmology · Physics 2021-02-19 John D. Barrow , Spyros Basilakos , Emmanuel N. Saridakis

Assuming the lightest neutralino forms dark matter, we study its residual annihilation after freeze-out at the early universe. If taking place after the big bang nucleosynthesis (BBN) the annihilation products, especially at the hadronic…

High Energy Physics - Phenomenology · Physics 2008-04-17 Xiao-Jun Bi

A dark radiation term arises as a correction to the energy momentum tensor in the simplest five-dimensional RS-II brane-world cosmology. In this paper we revisit the constraints on dark radiation based upon the newest results for…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-08 Nishanth Sasankan , Mayukh R. Gangopadhyay , Grant J. Mathews , Motohiko Kusakabe
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