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arXiv · hep-ph/9805302

Electroweak Baryogenesis in the Presence of an Isosinglet Quark

G. C. Branco·D. Delepine·D. Emmanuel-Costa·R. Gonzalez Felipe
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Abstract

We consider the possibility of electroweak baryogenesis in a simple extension of the standard model with an extra singlet complex scalar and a vector-like down quark. We show that in the present model the first-order electroweak phase transition can be strong enough to avoid the baryon asymmetry washout by sphalerons and that the CP-violating effects can be sufficient to explain the observed baryon-to-entropy ratio nB/s ~ 10^(-10). Other appealing features of the model include the generation of a CKM phase from spontaneous CP breaking at a high energy scale and a possible solution of the strong CP problem through the natural suppression of the parameter theta.

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G. C. Branco, D. Delepine, D. Emmanuel-Costa, R. Gonzalez Felipe. 1998-05-12. Electroweak Baryogenesis in the Presence of an Isosinglet Quark. https://doi.org/10.1016/s0370-2693(98)01253-2

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