Be-7 (n,p)Li-7 Reaction and the Cosmological Lithium Problem

Autor(en)

, L. Damone, M. Barbagallo, M. Mastromarco, A. Mengoni, L. Cosentino, E. Maugeri, S. Heinitz, D. Schumann, R. Dressler, F. Käppeler, N. Colonna, P. Finocchiaro, J. Andrzejewski, J. Perkowski, A. Gawlik, O. Aberle, S. Altstadt, M. Ayranov, L. Audouin, M. Bacak, J. Balibrea-Correa, J. Ballof, V. Becares, F. Becvar, C. Beinrucker, G. Bellia, A. P. Bernardes, E. Berthoumieux, J. Billowes, M. J. G. Borge, D. Bosnar, A. Brown, M. Brugger, M. Busso, M. Caamano, F. Calvino, M. Calviani, D. Cano-Ott, R. Cardella, A. Casanovas, D. M. Castelluccio, Y. H. Chen, H. Leeb, M. Mirea, A. Pavlik, S. Schmidt, A. Wallner, C. Weiss, C. Wolf, T. Wright

Abstrakt

We report on the measurement of the Be-7(n,p)Li-7 cross section from thermal to approximately 325 keV neutron energy, performed in the high-flux experimental area (EAR2) of the n_TOF facility at CERN. This reaction plays a key role in the lithium yield of the big bang nucleosynthesis (BBN) for standard cosmology. The only two previous time-of-flight measurements performed on this reaction did not cover the energy window of interest for BBN, and they showed a large discrepancy between each other. The measurement was performed with a Si telescope and a high-purity sample produced by implantation of a Be-7 ion beam at the ISOLDE facility at CERN. While a significantly higher cross section is found at low energy, relative to current evaluations, in the region of BBN interest, the present results are consistent with the values inferred from the time-reversal Li-7(p,n)Be-7 reaction, thus yielding only a relatively minor improvement on the so-called cosmological lithium problem. The relevance of these results on the near-threshold neutron production in the p + Li-7 reaction is also discussed.

Organisation(en)

Isotopenphysik

Externe Organisation(en)

Università degli Studi di Bari, European Organization for Nuclear Research (CERN), Paul Scherrer Institute, Karlsruher Institut für Technologie, Medical University of Lodz, Johann Wolfgang Goethe-Universität Frankfurt am Main, European Commission, Centre National De La Recherche Scientifique (CNRS), Technische Universität Wien, Centro de Investigaciones Energeticas Medioambientales y Tecnológica, Charles University Prague, Università degli Studi di Catania, French Alternative Energies and Atomic Energy Commission (CEA), University Hospital Centre Zagreb, Università degli Studi di Perugia, Universidade de Santiago de Compostela (USC), Universitat Politècnica de Catalunya, Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering, Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Bari, Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Bologna, Agenzia nazionale per le nuove tecnologie, l’energia e lo sviluppo economico sostenibile, INFN Laboratori Nazionali del Sud, University of York, Universität Wien, Australian National University, University of Manchester, Centre National de la Recherche Scientifique (CNRS), Strasbourg , Central Manchester University Hospitals, Instituto Nazionale di Fisica Nucleare

Journal

Physical Review Letters

Band

121

Anzahl der Seiten

7

ISSN

0031-9007

DOI

https://doi.org/10.1103/PhysRevLett.121.042701

Publikationsdatum

07-2018

Peer-reviewed

Ja

ÖFOS 2012

103014 Kernphysik

Schlagwörter

ASJC Scopus Sachgebiete

Physics and Astronomy(all)

Link zum Portal

https://ucris.univie.ac.at/portal/de/publications/be7-npli7-reaction-and-the-cosmological-lithium-problem(eec743db-25bd-4e6a-adf2-ce9f265afd6d).html