出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：The 18F nucleus is one of the radioactive isotopes produced during nova explosions. It is of
particular interest since it is mainly responsible for the 511 keV gamma-ray emission of novae
that could be detected with the INTEGRAL satellite or future gamma-ray telescopes. The amount
of 18F synthesised still suffers from large uncertainties coming from missing nuclear information
concerning the 18F destruction reaction 18F(p,a)15O. In particular, the interference sign between
three 3/2+ resonances in 19Ne, situated slightly above the proton threshold (8 keV and/or 38
keV) and at higher energy (665 keV), is unknown. The maximum effect of these interferences is
lying in the energy range corresponding to the Gamow peak region and has a strong impact on
the 18F(p,a)15O reaction rate. We report here on the direct measurement at low energy (down
to 400 keV in the center-of-mass) of the 18F(p,a)15O total cross section that we performed at
the Louvain-la-Neuve CRC-RIB facility with the high-intensity and -purity 18F radioactive beam
(T1/2 = 110 min). The total cross section for the different incident energies will be presented and
compared to previous experimental data.
