Eur. Phys. J. Plus (2012) 127: 158
https://doi.org/10.1140/epjp/i2012-12158-y

Regular Article

Rare top decay t → cl⁺l⁻ in economical 331 models

¹ Departamento de Física, FES-Cuautitlán, UNAM, C.P. 54770, Estado de México, Mexico
² Departamento de Física, Universidad Nacional de Colombia, Bogotá D.C., Colombia

^* e-mail: rgaitan@unam.mx

Received: 1 October 2012
Accepted: 13 November 2012
Published online: 21 December 2012

Abstract

The models based on SU(3) _C × SU(3) _L × U(1) _X gauge symmetry group contain an interesting source of flavor-changing neutral current at tree level. These models are known as the 331 models in the literature. The third quark family can transform differently from the first and second quark families in the 331 models. Then, flavor-changing neutral current arises from the interaction with quarks with the new neutral gauge boson, Z′. Using this coupling we estimated the partial decay width for the rare top decay t → cl ⁺ l ⁻. We find that the corresponding branching fraction can be around 10⁻¹²−10⁻⁹ for 1 TeV ≤ M _Z′ ≤ 5 TeV with mixing angle of quarks eigenstates between 0.1 and 0.5.