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Scientific paper - Original scientific paper
7Be(n, α)4He Reaction and the Cosmological Lithium Problem: Measurement of the Cross Section in a Wide Energy Range at n_TOF at CERN
Physical Review Letters, 117 (2016), 15; 152701. https://doi.org/10.1103/PhysRevLett.117.152701
(n_TOF Collaboration) Barbagallo, M.; ...; Bosnar, Damir; ...; Žugec, Petar

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Barbagallo, M., Bosnar, D. & Žugec, P. (2016). 7Be(n, α)4He Reaction and the Cosmological Lithium Problem: Measurement of the Cross Section in a Wide Energy Range at n_TOF at CERN. Physical Review Letters, 117. (15). doi: 10.1103/PhysRevLett.117.152701

Barbagallo, M., et al. "7Be(n, α)4He Reaction and the Cosmological Lithium Problem: Measurement of the Cross Section in a Wide Energy Range at n_TOF at CERN." Physical Review Letters, vol. 117, no. 15, 2016. https://doi.org/10.1103/PhysRevLett.117.152701

Barbagallo, M., Damir Bosnar and Petar Žugec. "7Be(n, α)4He Reaction and the Cosmological Lithium Problem: Measurement of the Cross Section in a Wide Energy Range at n_TOF at CERN." Physical Review Letters 117, no. 15 (2016). https://doi.org/10.1103/PhysRevLett.117.152701

Barbagallo, M., Bosnar, D. and Žugec, P. (2016) '7Be(n, α)4He Reaction and the Cosmological Lithium Problem: Measurement of the Cross Section in a Wide Energy Range at n_TOF at CERN', Physical Review Letters, 117(15). doi: 10.1103/PhysRevLett.117.152701

Barbagallo M, Bosnar D, Žugec P. 7Be(n, α)4He Reaction and the Cosmological Lithium Problem: Measurement of the Cross Section in a Wide Energy Range at n_TOF at CERN. Physical Review Letters [Internet]. 2016 [cited 2024 November 27];117(15). doi: 10.1103/PhysRevLett.117.152701

M. Barbagallo, D. Bosnar and P. Žugec, "7Be(n, α)4He Reaction and the Cosmological Lithium Problem: Measurement of the Cross Section in a Wide Energy Range at n_TOF at CERN", Physical Review Letters, vol. 117, no. 15, 2016. [Online]. Available at: https://urn.nsk.hr/urn:nbn:hr:217:940116. [Accessed: 27 November 2024]

Metadata
Title (english)7Be(n, α)4He Reaction and the Cosmological Lithium Problem: Measurement of the Cross Section in a Wide Energy Range at n_TOF at CERN
AuthorM. Barbagallo
Author
...
AuthorDamir Bosnar
MBZ: 134936
Author
...
AuthorPetar Žugec
MBZ: 326085
Collaborationn_TOF Collaboration
Author's institutionUniversity of Zagreb
Faculty of Science
(Department of Physics)
Scientific / art field,
discipline and subdiscipline		NATURAL SCIENCES
Physics
Abstract (english)
The energy-dependent cross section of the 7Be(n, α)4He reaction, of interest for the so-called cosmological lithium problem in big bang nucleosynthesis, has been measured for the first time from 10 meV to 10 keV neutron energy. The challenges posed by the short half-life of 7Be and by the low reaction cross section have been overcome at n_TOF thanks to an unprecedented combination of the extremely high luminosity and good resolution of the neutron beam in the new experimental area (EAR2) of the n_TOF facility at CERN, the availability of a sufficient amount of chemically pure 7Be, and a specifically designed experimental setup. Coincidences between the two alpha particles have been recorded in two Si-7Be-Si arrays placed directly in the neutron beam. The present results are consistent, at thermal neutron energy, with the only previous measurement performed in the 1960s at a nuclear reactor. The energy dependence reported here clearly indicates the inadequacy of the cross section estimates currently used in BBN calculations. Although new measurements at higher neutron energy may still be needed, the n_TOF results hint at a minor role of this reaction in BBN, leaving the long-standing cosmological lithium problem unsolved.
Keywords (english)
Languageenglish
Publication typeScientific paper - Original scientific paper
Publication statusPublished
Peer reviewPeer review - international
Publication versionPublished version
Journal titlePhysical Review Letters
Numberingvol. 117, no. 15, 152701
p-ISSN0031-9007
DOIhttps://doi.org/10.1103/PhysRevLett.117.152701
URN:NBNurn:nbn:hr:217:940116
Publication2016
ProjectNumber: IP-2013-11-1680
Title (croatian): Precizna mjerenja svojstava hadronskih sustava i niskoenergijska QCD
Acronym: PExpQCD
Leader: Damir Bosnar
Jurisdiction: Croatia
Funding stream: IP
Document URLhttps://journals.aps.org/prl/abstract/10.1103/PhysRevLett.117.152701
Type of resourceText
Access conditionsOpen access
Terms of useLicence Attribution 3.0 Unported (CC BY 3.0) icon
Public note© 2016 American Physical Society. This article is available under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Received 22 June 2016; revised manuscript received 12 August 2016; published 3 October 2016.
Created on2020-02-23 19:56:33