2000/06/27 by Jan B. Rehm, Karsten Jedamzik · 1 citation
Physics and Astronomy · #Antimatter #Astrophysics #Baryogenesis #Baryon #Big Bang (financial markets) #Big Bang nucleosynthesis #Cosmic ray #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Dark matter #Lepton #Nuclear physics #Nuclear reaction #Nucleosynthesis #Particle physics #Particle physics theoretical and experimental studies #Physics #Universe #astro-ph #hep-ph
paper · pdf · doi:10.1103/physrevd.63.043509
published as Phys.Rev. D63 (2001) 043509 · 22 pages, 12 .ps figures included, revtex, submitted to PRD, also available at http://www.mpa-garching.mpg.de/~jan/bbn/bbn.html
arxiv created 2000/06/27 · openalex publication_date 2001/01/30 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We present detailed numerical calculations of the light element abundances synthesized in a universe consisting of matter and antimatter domains, as predicted to arise in some electroweak baryogenesis scenarios. In our simulations all relevant physical effects, such as baryon-antibaryon annihilations, production of secondary particles during annihilations, baryon diffusion, and hydrodynamic processes, are coupled to the nuclear reaction network. We identify two dominant effects, according to the typical spatial dimensions of the domains. Small antimatter domains are dissipated via neutron diffusion prior to 4He synthesis at T_4He\ensuremath≈80keV, leading to a suppression of the primordial 4He mass fraction. Larger domains are dissipated below T_4He via a combination of proton diffusion and hydrodynamic expansion. In this case the strongest effects on the elemental abundances are due to p4He annihilations, leading to an overproduction of 3He relative to 2H and to an overproduction of 6Li via nonthermal nuclear reactions. Both effects may result in light element abundances deviating substantially from the standard big bang nucleosynthesis yields and from the observationally inferred values. This allows us to derive stringent constraints on the antimatter parameters. For some combinations of the parameters, one may obtain both low 2H and low 4He at a common value of the cosmic baryon density, a result seemingly favored by current observational data.