Towards a viable scalar interpretation of RD(*)

Sean Fraser, Carlo Marzo, Luca Marzola, Martti Raidal, Christian Spethmann
2018 Physical Review D  
Recent measurements of semileptonic B-meson decays seemingly imply violations of lepton flavor universality beyond the Standard Model predictions. With three-level explanations based on extended Higgs sectors being strongly challenged by the measurements of the B_c^- lifetime, new theories invoking leptoquark or vector fields appear as the only feasible answer. However, in this work we show that simple scalar extensions of the Standard Model still offer a possible solution to the B physics
more » ... e, owing to sizeable loop-level corrections which mimic the effects of new vector contributions. Considering a simplified model characterised by a charged and a neutral scalar particle, we verify the compatibility of the observed R_D^(*) signal with the relevant collider bounds. We also study an embedding of the simplified model into a three-Higgs-doublet framework, and investigate its main phenomenological constraints.
doi:10.1103/physrevd.98.035016 fatcat:hwyc2hzzfrfnvcbhqhas44m5wy