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arXiv · 1808.07893

Measurement of $d + ^7$Be cross sections for Big-Bang nucleosynthesis

N. Rijal·I. Wiedenhöver·J. C. Blackmon·M. Anastasiou·L. T. Baby·D. D. Caussyn·P. Höflich·K. W. Kemper·E. Koshchiy·G. V. Rogachev
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Abstract

The cross sections of nuclear reactions between the radioisotope $^7$Be and deuterium, a possible mechanism of reducing the production of mass-7 nuclides in Big-Bang nucleosynthesis, were measured at center-of-mass energies between 0.2 MeV and 1.5 MeV. The measured cross sections are dominated by the $(d,α)$ reaction channel, towards which prior experiments were mostly insensitive. A new resonance at 0.36(5)~MeV with a strength of $ωγ$ = 1.7(5)~keV was observed inside the relevant Gamow window. Calculations of nucleosynthesis outcomes based on the experimental cross section show that the resonance reduces the predicted abundance of primordial $^7$Li, but not sufficiently to solve the primordial lithium problem.

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N. Rijal, I. Wiedenhöver, J. C. Blackmon, M. Anastasiou, L. T. Baby, D. D. Caussyn, P. Höflich, K. W. Kemper, E. Koshchiy, G. V. Rogachev. 2018-12-11. Measurement of $d + ^7$Be cross sections for Big-Bang nucleosynthesis. https://doi.org/10.1103/physrevlett.122.182701

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