Temperature Dependence of Standard Model CP Violation
Oct, 2011
Citations per year
Abstract: (arXiv)
We analyze the temperature dependence of CP violation effects in the Standard Model by determining the effective action of its bosonic fields, obtained after integrating out the fermions from the theory and performing a covariant gradient expansion. We find non-vanishing CP violating terms starting at the sixth order of the expansion, albeit only in the C odd/P even sector, with coefficients that depend on quark masses, CKM matrix elements, temperature and the magnitude of the Higgs field. The CP violating effects are observed to decrease rapidly with temperature, which has important implications for the generation of a matter-antimatter asymmetry in the early Universe. Our results suggest that the cold electroweak baryogenesis scenario may be viable within the Standard Model, provided the electroweak transition temperature is at most of order 1 GeV.Note:
- 4 pages, 2 figures. Additional non-trivial cancellations lead to vanishing of P-odd sector also at finite temperature. Minor additional modifications and clarifications, conclusions otherwise unchanged. Published version
- 11.30.Er
- 11.10.Wx
- 98.80.Bp
References(27)
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