2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/194586We study the complete one-loop contributions to the chromagnetic dipole moment $Δκ$ of the top quark in the Standard Model, two Higgs doublet models, topcolor assited technicolor models (TC2), 331 models and extended models with a single extra dimension. We find that the SM predicts $Δκ= - 0.056$ and that the predictions of the other models are also consitent with the constraints imposed on $Δκ$ by low-energy precision measurements.20 pages, 5 figures, UpdateHigh Energy Physics - Phenomenologytext