Flavor constraints for a vector-like quark of Nelson-Barr type

Abstract The Nelson-Barr (NB) mechanism to solve the strong CP problem assumes CP conservation, arranges vanishing θ ¯ $$ \overline{\theta} $$ at tree-level and requires vector-like quarks (VLQs) to transmit the CP breaking to the SM. We analyze the flavor constraints coming from the presence of one...

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Detalhes bibliográficos
Main Authors: A. L. Cherchiglia, G. De Conto, C. C. Nishi
Formato: Artigo
Idioma:English
Publicado em: SpringerOpen 2021-11-01
Colecção:Journal of High Energy Physics
Assuntos:
Acesso em linha:https://doi.org/10.1007/JHEP11(2021)093
Descrição
Resumo:Abstract The Nelson-Barr (NB) mechanism to solve the strong CP problem assumes CP conservation, arranges vanishing θ ¯ $$ \overline{\theta} $$ at tree-level and requires vector-like quarks (VLQs) to transmit the CP breaking to the SM. We analyze the flavor constraints coming from the presence of one such down type VLQ of NB type by performing a global fit on the relevant flavor observables. A comparison is made to the case of one generic VLQ. We find that the allowed parameter space for the VLQ Yukawa couplings and the mixing to the SM are confined to a region much smaller than in the generic case, making the NB case falsifiable in principle.
ISSN:1029-8479