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Unveiling the dynamics of little-bang nucleosynthesis
Kai-Jia Sun1,2, Rui Wang3,4, Che Ming Ko5
1Key Laboratory of Nuclear Physics and Ion-beam Application (MOE), Institute of Modern Physics, Fudan University, Shanghai, 200433, China. kjsun@fudan.edu.cn.
Nature Communications
|February 5, 2024
Summary
High-energy nuclear collisions create quark-gluon plasma. Later interactions, particularly pion-catalyzed reactions, significantly reduce triton yields, impacting early universe nucleosynthesis models.
Area of Science:
- Nuclear physics
- Particle physics
- Cosmology
Background:
- High-energy nuclear collisions simulate early universe conditions.
- Quark-gluon plasma (QGP) is created at temperatures of ~100-150 MeV.
- Previous models suggested light nuclei abundances are stable post-QGP.
Purpose of the Study:
- Investigate the role of hadronic dynamics on light nuclei production.
- Quantify the effect of secondary interactions on triton yields.
- Re-evaluate early universe nucleosynthesis models.
Main Methods:
- Kinetic approach incorporating hadronic re-scatterings.
- Focus on pion-catalyzed multi-body reactions.
- Comparison with experimental data from heavy-ion collisions.
Main Results:
- Triton yield is reduced by approximately a factor of 1.8.
- Hadronic re-scatterings significantly influence light nuclei abundances.
- Pion-catalyzed reactions play a crucial role.
Conclusions:
- Hadronic dynamics are critical in 'little bang' nucleosynthesis.
- Triton yield reduction challenges previous assumptions.
- Findings align with recent experimental observations.
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