CP Violation and Electroweak Baryogenesis in SMEFT

  Yehonatan Viernik  ,  Elina Fuchs  ,  Marta Losada  ,  Yosef Nir  
Weizmann Institute

We explore the implications of the Standard Model effective field theory with dimension-
six terms involving the Higgs boson and third generation fermion fields on the rate of Higgs boson
production and decay into fermions, on electric dipole moments (EDMs) of leptons, and on the
baryon asymmetry of the Universe. We study the consequences of allowing these additional terms
for each flavor separately and for combinations of two flavors. We find that a complex τ Yukawa
coupling can account for the observed baryon asymmetry within LHC and EDM bounds. A
complex b (t) Yukawa coupling can account for 4% (2%) of the asymmetry, whereas a combination of the
two can reach 12%. Combining τ with either t or b enlarges the viable parameter space owing to
cancelations in the EDM and in Higgs production times decay or the total Higgs width, respectively.