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arXiv · hep-ph/9406289

Standard Model CP-violation and Baryon asymmetry Part II: Finite Temperature

M. B. Gavela·P. Hernandez·J. Orloff·O. Pène·C. Quimbay
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Abstract

We consider the scattering of quasi-particles off the boundary created during a first order electroweak phase transition. Spatial coherence is lost due to the quasi-quark damping rate, and we show that reflection on the boundary is suppressed, even at tree-level. Simply on CP considerations, we argue against electroweak baryogenesis in the Standard Model via the charge transport mechanism. A CP asymmetry is produced in the reflection properties of quarks and antiquarks hitting the phase boundary. An effect is present at order $α_W^2$ in rate and a regular GIM behaviour is found, which can be expressed in terms of two unitarity triangles. A crucial role is played by the damping rate of quasi-particles in a hot plasma, which is a relevant scale together with $M_W$ and the temperature. The effect is many orders of magnitude below what observation requires.

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M. B. Gavela, P. Hernandez, J. Orloff, O. Pène, C. Quimbay. 1994-06-12. Standard Model CP-violation and Baryon asymmetry Part II: Finite Temperature. https://doi.org/10.1016/0550-3213(94)00410-2

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