Photodisintegration of the Deuteron between Eγ = 2.4 and 4.0 MeV
Big-bang nucleosynthesis (BBN) is an observational cornerstone of the hot big-bang cosmology. According to  the p(n,γ)d reaction is of special interest because the big-bang abundance of deuterium is most sensitive to the baryon density. However, in the most important energy range for BBN, i.e., from 25–200 keV in the c.m. system, experimental data are completely missing. In fact, published data exist only at thermal energies and at n-p c.m. energies above 275 keV. Therefore, theoretical models have been used  in the BBN energy range that are normalized to the high-precision thermal neutron capture cross-section data.