Neutrinos and Big Bang Nucleosynthesis
Author
Source
Advances in High Energy Physics
Issue
Vol. 2012, Issue 2012 (31 Dec. 2012), pp.1-24, 24 p.
Publisher
Hindawi Publishing Corporation
Publication Date
2012-12-27
Country of Publication
Egypt
No. of Pages
24
Main Subjects
Abstract EN
According to the standard models of particle physics and cosmology, there should be a background of cosmic neutrinos in the present Universe, similar to the cosmic microwave photon background.
The weakness of the weak interactions renders this neutrino background undetectable with current technology.
The cosmic neutrino background can, however, be probed indirectly through its cosmological effects on big bang nucleosynthesis (BBN) and the cosmic microwave background (CMB) radiation.
In this BBN review, focused on neutrinos and more generally on dark radiation, the BBN constraints on the number of “equivalent neutrinos” (dark radiation), on the baryon asymmetry (baryon density), and on a possible lepton asymmetry (neutrino degeneracy) are reviewed and updated.
The BBN constraints on dark radiation and on the baryon density following from considerations of the primordial abundances of deuterium and helium-4 are in excellent agreement with the complementary results from the CMB, providing a suggestive, but currently inconclusive, hint of the presence of dark radiation, and they constrain any lepton asymmetry.
For all the cases considered here there is a “lithium problem”: the BBN-predicted lithium abundance exceeds the observationally inferred primordial value by a factor of ~3.
American Psychological Association (APA)
Steigman, Gary. 2012. Neutrinos and Big Bang Nucleosynthesis. Advances in High Energy Physics،Vol. 2012, no. 2012, pp.1-24.
https://search.emarefa.net/detail/BIM-458908
Modern Language Association (MLA)
Steigman, Gary. Neutrinos and Big Bang Nucleosynthesis. Advances in High Energy Physics No. 2012 (2012), pp.1-24.
https://search.emarefa.net/detail/BIM-458908
American Medical Association (AMA)
Steigman, Gary. Neutrinos and Big Bang Nucleosynthesis. Advances in High Energy Physics. 2012. Vol. 2012, no. 2012, pp.1-24.
https://search.emarefa.net/detail/BIM-458908
Data Type
Journal Articles
Language
English
Notes
Includes bibliographical references
Record ID
BIM-458908