Big Bang Nucleosynthesis Revisited via Trojan Horse Method Measurements

Abstract

Nuclear reaction rates are among the most important input for understanding the primordial nucleosynthesis and therefore for a quantitative description of the early Universe. An up-to-date compilation of direct cross sections of 2 H(d,p) 3 H, 2 H(d,n) 3 He, 7 Li(p,α) 4 He and 3 He(d,p) 4 He reactions is given. These are among the most uncertain cross sections used and input for Big Bang nucleosynthesis calculations. Their measurements through the Trojan Horse Method (THM) are also reviewed and compared with direct data. The reaction rates and the corresponding recommended errors in this work were used as input for primordial nucleosynthesis calculations to evaluate their impact on the 2 H, 3,4 He and 7 Li primordial abundances, which are then compared with observations.

ASTROPHYSICAL IMPACT OF THE UPDATED9Be(p,α)6Li AND10B(p,α)7Be REACTION RATES AS DEDUCED BY THM

“…In recent years, THM data allowed for a better understanding of different astrophysical problems, such as the study of light element burning reactions (Pizzone et al 2005(Pizzone et al , 2014Lamia et al 2008Lamia et al , 2012bLamia et al , 2012cLamia et al , 2013Tumino et al 2011aTumino et al , 2011bTumino et al , 2014Grineviciute et al 2015), CNO reactions (see La Cognata et al 2010Sergi et al 2010;Palmerini et al 2013), and removing/producing neutron reactions (Lamia et al 2008;Gulino et al 2010Gulino et al , 2013La Cognata et al 2012). …”

Fusion reactions induced by radioactive beams: the18F(p,α)15O case

“…The THM allows one to avoid both Coulomb barrier suppression and electron screening effects, thus preventing the use of extrapolations. The method has proven very helpful in the last two decades for application to several aspects of nuclear astrophysics research like primordial nucleosynthesis [16][17][18], AGB nucleosynthesis [19,20], the lithium problem [21][22][23], light elements depletion in stars [24,25]. It has also been used with neutron induced reactions [26].…”

“…18 F appears to be produced in the novae inner shells via the Hot-CNO cycle according to several authors [2]. In particular the production path goes through: 16 be measured in the astrophysically relevant Gamow window [4], of the order of few hundreds keV (corresponding to 0.05≤T 9 ≤0.5).…”

Current Status of Nuclear Physics Research

“…The THM data are renormalized to those obtained with direct methods at high energies and the data at low energies are obtained as a bonus. The THM has been applied to a large number of reactions of interest for the production of light elements in numerous stellar environments to reactions of interest for the BBN [347]. One of the many advantages of using transfer reaction techniques over direct measurements is to avoid the treatment of the electron screening problem [348][349][350].…”