Leptogenesis via Varying Weinberg Operator: the Closed-Time-Path Approach

Turner, Jessica; Zhou, Ye-Ling

Abstract

In this work we provide a detailed study of the CP violating phase transition (CPPT) which is a new mechanism proposed to produce a baryon asymmetry. This mechanism exploits the Weinberg operator whose coefficient is dynamically realised from the vacuum expectation values (VEVs) of new scalars. In the specific case of the first order phase transition, the scalar VEVs vary in the bubble wall which separates the two phases. This results in a spacetime varying coefficient for the Weinberg operator. The interference of two Weinberg operators at different spacetime points generates a CP asymmetry between lepton and anti-lepton production/annihilation processes, which eventually results in an asymmetry between baryon and anti-baryon number densities in the early Universe. We present the calculation of the lepton asymmetry, based on non-equilibrium quantum field theory methods, in full. We consider the influence of the bubble wall characteristics and the impact of thermal effects on the lepton asymmetry and draw a comparison between the CPPT mechanism and electroweak baryogenesis.

Citation

Turner, J., & Zhou, Y.-L. (2020). Leptogenesis via Varying Weinberg Operator: the Closed-Time-Path Approach. Journal of High Energy Physics, 2020, Article 22. https://doi.org/10.1007/jhep01%282020%29022

• Journal Article Type: Article
• Acceptance Date: Dec 13, 2019
• Online Publication Date: Jan 7, 2020
• Publication Date: Jan 31, 2020
• Deposit Date: Sep 25, 2018
• Publicly Available Date: Jan 19, 2020
• Journal: Journal of High Energy Physics
• Print ISSN: 1126-6708
• Publisher: Scuola Internazionale Superiore di Studi Avanzati (SISSA)
• Peer Reviewed: Peer Reviewed
• Volume: 2020
• Article Number: 22
• DOI: https://doi.org/10.1007/jhep01%282020%29022
• Public URL: https://durham-repository.worktribe.com/output/1318710
• Related Public URLs: arXiv:1808.00470