Electroweak baryogenesis and the standard model effective field theory
Jordy Vries (Nikhef, Theory Group, Science Park 105, Amsterdam, 1098 XG, The Netherlands); Marieke Postma (Nikhef, Theory Group, Science Park 105, Amsterdam, 1098 XG, The Netherlands); Jorinde Vis (Nikhef, Theory Group, Science Park 105, Amsterdam, 1098 XG, The Netherlands); Graham White (ARC Centre of Excellence for Particle Physics at the Terascale School of Physics and Astronomy, Monash University, Victoria, 3800, Australia, TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia, V6T 2A3, Canada)
We investigate electroweak baryogenesis within the framework of the Standard Model Effective Field Theory. The Standard Model Lagrangian is supplemented by dimension-six operators that facilitate a strong first-order electroweak phase transition and provide sufficient CP violation. Two explicit scenarios are studied that are related via the classical equations of motion and are therefore identical at leading order in the effective field theory expansion. We demonstrate that formally higher-order dimension-eight corrections lead to large modifications of the matter-antimatter asymmetry. The effective field theory expansion breaks down in the modified Higgs sector due to the requirement of a first-order phase transition. We investigate the source of the breakdown in detail and show how it is transferred to the CP-violating sector. We briefly discuss possible modifications of the effective field theory framework.
