TY  - JOUR
AU  - n_TOF Collaboration (Damone, L. et al
AU  - Domingo-Pardo, C.
AU  - Tain, J. L.
AU  - Tarifeño-Saldivia, A.
PY  - 2018
DA  - 2018//
TI  - Be-7 (n,p)Li-7 Reaction and the Cosmological Lithium Problem: Measurement of the Cross Section in a Wide Energy Range at n_TOF at CERN
T2  - Phys. Rev. Lett.
JO  - Physical Review Letters
SP  - 042701
EP  - 7pp
VL  - 121
IS  - 4
PB  - Amer Physical Soc
AB  - 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.
SN  - 0031-9007
UR  - http://arxiv.org/abs/1803.05701
UR  - https://doi.org/10.1103/PhysRevLett.121.042701
DO  - 10.1103/PhysRevLett.121.042701
LA  - English
N1  - WOS:000439547100004
ID  - n_TOFCollaborationDamone_etal2018
ER  -