DATA: 04-12-2017

The 3He(alpha,gamma)7Be reaction is the starting point of the ppII and ppIII reaction branches in the solar hydrogen burning, therefore its rate has sizeable impact on the solar 7Be and 8B neutrino production. It has also considerable impact on the production of 7Li in the big bang nucleosynthesis (BBN). Many experiments have been done since the turn of the century clearing up some long standing issues regarding the 3He(alpha,gamma)7Be reaction [1,2], but this reaction rate is still one of the most uncertain solar rates. Most of the reaction cross section measurements concentrated on the low energies and their precision mostly reached the limits. However, there is no experimental data above Ecm = 3.1 MeV. It was suggested recently, that the R-matrix models have to be tested with higher energy datasets [3]. In addition, there are conflicting datasets for the 6Li(p,gamma)7Be reaction [4,5] having impact on the level scheme of 7Be. We measured the 3He(alpha,gamma)7Be reaction cross section with the activation technique in a wide energy range between Ecm = 2.5-4.4 MeV. The lower part of the investigated energy range contains data points from previous measurements [9] to have a possible direct comparisons with other works. The higher part extends above the proton separation energy of 7Be, thus it can be compared also with the 6Li(p,gamma)7Be reaction cross sections. [1] E. G. Adelberger et al., Rev. Mod. Phys. 70, 1265 (1998); [2] E. G. Adelberger et al., Rev. Mod. Phys. 83, 195 (2011); [3] R. J. deBoer et al., Phys. Rev. C 90, 035804 (2014); [4] R. M. Prior et al., Phys. Rev. C 70, 055801 (2004); [5] J. He et al., Phys. Lett. B 725, 287 (2013); [6] C. Bordeanu et al., Nucl. Phys. A 908, 1 (2013). --- Tamas Szcs Institute for Nuclear Research (MTA Atomki) Debrecen, Hungary


09-12-2019: Visita ai laboratori della Sezione INFN di Trieste da parte di studenti del Liceo Scientifico dell' IIS Cattaneo-Dall'Aglio di Castelnovo ne' Monti (RE)
09-12-2019: Properties of nuclei in the N=Z=50 region investigated via multi-nucleon transfer reactions and lifetime measurements - Marco Siciliano
06-12-2019: From kaonic atoms to strangeness in neutron stars
05-12-2019: M. Gromov - Updated results of the geo-neutrino observation with the Borexino detector
05-12-2019: A scuola di radioattivita'
04-12-2019: La fisica incontra la citt - L'arte ed i suoi segreti: la fisica per svelarli
04-12-2019: Nuclei per l'ambiente
04-12-2019: A. Melchiorri - A crisis in lalalambda land?
02-12-2019: MariX: Conceptual Design Report of a Multi-disciplinary Advanced Research Infrastructure for the generation and application of X-rays
28-11-2019: Quantum Optical Control of Levitated Solids: a novel probe for the gravity-quantum interface





Istituto Nazionale di Fisica Nucleare - Piazza dei Caprettari, 70 - 00186 Roma
tel. +39 066840031 - fax +39 0668307924 - email: presidenza@presid.infn.it

F.M. F.E.