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arXiv · 1407.4566

Particle-antiparticle asymmetries from annihilations

Iason Baldes·Nicole F. Bell·Kalliopi Petraki·Raymond R. Volkas
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Abstract

An extensively studied mechanism to create particle-antiparticle asymmetries is the out-of-equilibrium and CP violating decay of a heavy particle. Here we instead examine how asymmetries can arise purely from 2 <-> 2 annihilations rather than from the usual 1 <-> 2 decays and inverse decays. We review the general conditions on the reaction rates that arise from S-matrix unitarity and CPT invariance, and show how these are implemented in the context of a simple toy model. We formulate the Boltzmann equations for this model, and present an example solution.

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Iason Baldes, Nicole F. Bell, Kalliopi Petraki, Raymond R. Volkas. 2014-11-03. Particle-antiparticle asymmetries from annihilations. https://doi.org/10.1103/physrevlett.113.181601

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