2025/04/15 by P. M. Ferreira, Ferreira, P. M., Pinto, Tomás F.
Physics and Astronomy · #Black Holes and Theoretical Physics #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.2504.11602
openalex publication_date 2025/04/15 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
A two-Higgs doublet model with a discrete Z3 symmetry acquires, in its scalar and gauge sectors, an accidental continuous U(1) symmetry. One therefore finds, after spontaneous symmetry breaking of those symmetries, that a massless pseudoscalar arises, as expected by Goldstone's theorem. In the fermion sector, however, it is possible to obtain Yukawa matrix textures which distinguish between the Z3 and U(1) symmetries, so one expects loop corrections to originate a non-zero pseudoscalar mass for the Z3 case. We perform an explicit calculation that shows that at one-loop the pseudoscalar remains massless for all but one tested Z3 Yukawa matrices. The pseudoscalar mass thus found is highly suppressed by the hierarchy of fermion masses.