Journal of High Energy Physics

, 2019:42 | Cite as

Unitarity and CP violation in leptogenesis at NLO: general considerations and top Yukawa contributions

  • J. RackerEmail author
Open Access
Regular Article - Theoretical Physics


With an emphasis on unitarity and CPT requirements, we study the inclusion of CP-violating processes in baryogenesis at next-to-leading order, particularly those involving the top Yukawa interaction in leptogenesis. We show that there are more contributions than previously considered, but also important cancellations. Some of these involve the interference of connected with disconnected diagrams. We also discuss on the application of the Kinoshita-Lee-Nauenberg theorem to treat the infrared divergences that are common at next-to-leading order. Finally, we calculate the CP asymmetry in the three-body decay of a sterile neutrino into a lepton and top quarks.


Cosmology of Theories beyond the SM Beyond Standard Model CP violation 


Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.


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© The Author(s) 2019

Authors and Affiliations

  1. 1.Instituto de Astronomía Teórica y Experimental (IATE), Universidad Nacional de Córdoba (UNC) — Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)CórdobaArgentina
  2. 2.Observatorio Astronómico de Córdoba (OAC)Universidad Nacional de Córdoba (UNC)CórdobaArgentina

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