Eur. Phys. J. C (2006) 46: 403-405
https://doi.org/10.1140/epjc/s2006-02507-9

Theoretical Physics

Improving bounds on flavor changing vertices in the two Higgs doublet model from mixing

¹ Departamento de Física, Universidad Nacional de Colombia, Bogotá, Colombia
² II. Institut für Theoretische Physik, Universität Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany

^* e-mail: radiazs@unal.edu.co

Received: 19 September 2005
Published online: 14 March 2006

Abstract

We find some constraints on the flavor changing vertices of the two Higgs doublet model, from the measurement. Although bounds from this observable have already been considered, this paper takes into account the role of a new operator not included previously, as well as the vertices , and . Using the Cheng–Sher parametrization, we find that for a relatively light charged Higgs boson (200–300 GeV), we obtain , while the parameter could have values up to about 50. In addition, we use bounds for and obtained from at next to leading order, and study the case where the only vanishing vertex factors are the ones involving quarks from the first family. We obtain that is not sensitive to the change of the parameter , while .