AbstractThe $${}^{5}$$
5
He($${}^{3}$$
3
He,$${}^{4}$$
4
He)$${}^{4}$$
4
He reaction involving the unstable $${}^{5}$$
5
He nucleus is a possible process in primordial nucleosynthesis to convert $${}^{3}$$
3
He into $${}^{4}$$
4
He in a neutron transfer reaction. Since experimental data for the reaction cross section are not available, a theoretical prediction is needed to estimate the relevance of this process in comparison to other reactions, e.g., $${}^{3}$$
3
He($${}^{2}$$
2
H,p)$${}^{4}$$
4
He or $${}^{3}$$
3
H($${}^{2}$$
2
H,n)$${}^{4}$$
4
He. In this work the cross section and the Maxwellian-averaged transition rate of the $${}^{5}$$
5
He($${}^{3}$$
3
He,$${}^{4}$$
4
He)$${}^{4}$$
4
He reaction are calculated using a post-form distorted-wave Born approximation in a simple cluster model. For that purpose the reaction is treated as a genuine process with three particles, $$\text{ n }+{}^{4}\text{ He }+{}^{3}\text{ He }$$
n
+
4
He
+
3
He
, in the entrance channel proceeding through the $$3/2^{-}$$
3
/
2
-
resonance in the $$n-{}^{4}$$
n
-
4
He scattering continuum.
Primordial nucleosynthesis with varying fundamental constants. Solutions to the lithium problem and the deuterium discrepancy
