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Big-Bang Nucleosynthesis
A critical review is given of the current status of cosmological nucleosynthesis. In the framework of the Standard Model with 3 types of relativistic neutrinos, the baryon-to-photon ratio, η, corresponding to the inferred primordial abundances of deuterium and helium-4 is consistent with the indepen...
Autores principales: | , , |
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Lenguaje: | eng |
Publicado: |
2014
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Materias: | |
Acceso en línea: | http://cds.cern.ch/record/2243492 |
_version_ | 1780953305163235328 |
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author | Fields, Brian D. Molaro, Paolo Sarkar, Subir |
author_facet | Fields, Brian D. Molaro, Paolo Sarkar, Subir |
author_sort | Fields, Brian D. |
collection | CERN |
description | A critical review is given of the current status of cosmological nucleosynthesis. In the framework of the Standard Model with 3 types of relativistic neutrinos, the baryon-to-photon ratio, η, corresponding to the inferred primordial abundances of deuterium and helium-4 is consistent with the independent determination of η from observations of anisotropies in the cosmic microwave background. However the primordial abundance of lithium-7 inferred from observations is significantly below its expected value. Taking systematic uncertainties in the abundance estimates into account, there is overall concordance in the range η=(5.7−6.7)×10−10 at 95% CL (corresponding to a cosmological baryon density ΩBh2=0.021−0.025). The D and He-4 abundances, when combined with the CMB determination of η, provide the bound Nν=3.28±0.28 on the effective number of neutrino species. Other constraints on new physics are discussed briefly. |
id | cern-1753419 |
institution | Organización Europea para la Investigación Nuclear |
language | eng |
publishDate | 2014 |
record_format | invenio |
spelling | cern-17534192021-05-03T20:31:32Zhttp://cds.cern.ch/record/2243492engFields, Brian D.Molaro, PaoloSarkar, SubirBig-Bang NucleosynthesisParticle Physics - ExperimentA critical review is given of the current status of cosmological nucleosynthesis. In the framework of the Standard Model with 3 types of relativistic neutrinos, the baryon-to-photon ratio, η, corresponding to the inferred primordial abundances of deuterium and helium-4 is consistent with the independent determination of η from observations of anisotropies in the cosmic microwave background. However the primordial abundance of lithium-7 inferred from observations is significantly below its expected value. Taking systematic uncertainties in the abundance estimates into account, there is overall concordance in the range η=(5.7−6.7)×10−10 at 95% CL (corresponding to a cosmological baryon density ΩBh2=0.021−0.025). The D and He-4 abundances, when combined with the CMB determination of η, provide the bound Nν=3.28±0.28 on the effective number of neutrino species. Other constraints on new physics are discussed briefly.arXiv:1412.1408oai:cds.cern.ch:17534192014 |
spellingShingle | Particle Physics - Experiment Fields, Brian D. Molaro, Paolo Sarkar, Subir Big-Bang Nucleosynthesis |
title | Big-Bang Nucleosynthesis |
title_full | Big-Bang Nucleosynthesis |
title_fullStr | Big-Bang Nucleosynthesis |
title_full_unstemmed | Big-Bang Nucleosynthesis |
title_short | Big-Bang Nucleosynthesis |
title_sort | big-bang nucleosynthesis |
topic | Particle Physics - Experiment |
url | http://cds.cern.ch/record/2243492 |
work_keys_str_mv | AT fieldsbriand bigbangnucleosynthesis AT molaropaolo bigbangnucleosynthesis AT sarkarsubir bigbangnucleosynthesis |