Bridging the primordial A=8 divide with Catalyzed Big Bang Nucleosynthesis

TL;DR

This paper explores how metastable charged particles could catalyze primordial nucleosynthesis, significantly increasing the production of ^9Be and providing a new way to test particle physics models through observed elemental abundances.

Contribution

It introduces a novel mechanism for primordial element synthesis via catalysis by metastable charged particles, extending standard Big Bang nucleosynthesis predictions.

Findings

Enhanced ^9Be production by orders of magnitude over standard BBN.

A specific relation between ^9Be and ^6Li abundances, ^9Be/^6Li = (2-5)×10^{-3}.

Potential for using ^9Be observations to probe particle physics models.

Abstract

Catalysis of nuclear reactions by metastable charged particles X^- opens the possibility for primordial production of elements with A>7. We calculate the abundance of ^9Be, where synthesis is mediated by the formation of (^8Be X^-) bound states, finding a dramatic enhancement over the standard BBN prediction: ^9Be/^1H = 10^{-13}\times(Y_X/10^{-5}). Thus observations of ^9Be abundances at low metallicity offers a uniquely sensitive probe of many particle physics models that predict X^-, including variants of supersymmetric models. Comparing the catalytically-enhanced abundances of primordial ^6Li and ^9Be, we find the relation ^9Be/^6Li = (2-5)\times 10^{-3} that holds over a wide range of X^- abundances and lifetimes.