Solving the cosmic lithium problems with primordial late-decaying particles

TL;DR

This paper explores how late-decaying particles in the early universe can resolve discrepancies between observed and predicted lithium abundances, providing a model-independent analysis that identifies viable parameter spaces.

Contribution

It introduces a model-independent framework to analyze the impact of long-lived particles on primordial nucleosynthesis, addressing lithium abundance problems.

Findings

Identifies parameter regions compatible with observational data

Shows late-decaying particles can reconcile Li7 and Li6 abundances

Provides constraints on particle properties from nucleosynthesis

Abstract

We investigate the modifications to predictions for the abundances of light elements from standard Big-Bang nucleosynthesis when exotic late-decaying particles with lifetimes exceeding ~1 sec are prominent in the early Universe. Utilising a model-independent analysis of the properties of these long-lived particles, we identify the parameter space associated with models that are consistent with all observational data and hence resolve the much discussed discrepancies between observations and theoretical predictions for the abundances of Li^7 and Li^6.