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H-dibaryons and Primordial Nucleosynthesis

J. A. de Freitas Pacheco·S. Stoica·F. Thevenin·J. E. Horvath
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Abstract

The apparent discrepancy between abundances of light nuclides predicted by the standard Big-Bang and observational data is explained, by assuming the presence of metastable H dibaryons at the nucleosynthesis era. These dibaryons could be formed out of a small fraction of strange quarks at the moment of the confinement transition. For a primordial deuterium abundance of the order of 3 10^{-5}, the measured differences in the 4He abundances requires a relative abundance of H dibaryons of the order of n_H/n_B = 0.07, decaying in a timescale of the order of 10^5 s.

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J. A. de Freitas Pacheco, S. Stoica, F. Thevenin, J. E. Horvath. 1998-10-19. H-dibaryons and Primordial Nucleosynthesis. https://doi.org/10.1103/physrevd.59.027303

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