Signatures of inhomogeneity in the early universe

Leading E1 and M1 contributions to radiative neutron capture on lithium-7

“…It also strongly constrains the 7 Be(p, γ) 8 B if mirror symmetry, which ought to have its origins in the (accidental) isospin symmetry of QCD, is invoked. Besides, n- 7 Li has its own astrophysical interest, bridging the path to the formation of heavier elements in inhomogeneous Big-Bang nucleosynthesis models [15]. The 7 Li(n, γ) 8 Li cross-section was calculated recently in effective field theory (EFT) for halo nuclei at low energy [16].…”

From Steam to Stars to the Early Universe

“…In this contribution I take the view that some of the chemical elements in thc halo were produced in the inflationary inhomogeneous stage of the early universe. This view is expressed in considerable detail in Kawano et al (1991). What follows is a modified version of that article.…”

“…It was determined that the bulk of the CNO production came through the 7Li(n, y)8Li(a, n)IIB(n, y) I2B(e�v) I2C etc, etc reaction sequence in the neutron-rich region. Kawano et al (1991) followed up this suggestion and looked at a more detailed reaction sequence for a wider range of parameters than hitherto studied, examining the relative importance of the 7Li(n, y)8Li reaction and the 7Li(a, y) II B reaction in the production of CNO elements. They also examined the path of heavy element production at I4C, looking at the relative importance of the I4C(n, y) I5C and I4C(p, y) I5N reactions as well as the I4C(d, n)I5N reaction which was included for the first time.…”

The origin and abundances of the chemical elements revisited

“…If the process is important, the early universe will contribute not only H, He, and Li 7, but also Be 9, CNO with non-solar isotope ratios, and even a bit of r-process material (Kawano et al 1990;Terasawa and Sato 1990). The disagreement arises over whether the amounts are likely (the Kellogg group) or unlikely (Terasawa and Sato 1990) to be detectable.…”