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arXiv · hep-ph/9603241

Solving the Crisis in Big-Bang Nucleosynthesis by the Radiative Decay of an Exotic Particle

Erich Holtmann·Masahiro Kawasaki·Takeo Moroi
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Abstract

We discuss a new mechanism which can solve the crisis in standard big-bang nucleosynthesis. A long-lived particle $X$ ($10^4 sec \lesssim τ_X \lesssim 10^6 sec$) which decays into photon(s) will induce cascade photons, and destroy significant amounts of D and $^3$He without destroying $^4$He or too much $^7$Li. We numerically investigate this process and derive a constraint on the properties of $X$ such that the theoretical values of the primordial light-element abundances agree with observation. We also present some candidates for the unstable particle $X$.

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Erich Holtmann, Masahiro Kawasaki, Takeo Moroi. 1996-10-15. Solving the Crisis in Big-Bang Nucleosynthesis by the Radiative Decay of an Exotic Particle. https://doi.org/10.1103/physrevlett.77.3712

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