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Charged Bilepton Pair Production at LHC Including Exotic Quark Contribution

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 Publication date 2008
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and research's language is English




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The production of $W^+ W^-$ pair in hadron colliders was calculated up to loop corrections by some authors in the Electroweak standard model (SM) framework. This production was also calculated, at the tree level, in some extensions of the SM such as the vector singlet, the fermion mirror fermion and the vector doublet models by considering the contributions of new neutral gauge bosons and exotic fermions. The obtained results for $e^+ e^-$ and $pp$ collisions pointed out that the new physics contributions are quite important. This motivates us to calculate the production of a more massive charged gauge boson predicted by the ${SU (3)_C times SU (3)_L times U (1)_X}$ model (3-3-1 model). Thus, the aim of the present paper is to analyze the role played by of the extra gauge boson ${Z^prime}$ and of the exotic quarks, predicted in the minimal version of the 3-3-1 model, by considering the inclusive production of a pair of bileptons ($V^pm$) in the reaction $p + p longrightarrow V^+ + V^- + X$, at the Large Hadron Collider (LHC) energies. Our results show that the correct energy behavior of the elementary cross section follows from the balance between the contributions of the extra neutral gauge boson with those from the exotic quarks. The extra neutral gauge boson induces flavor-changing neutral currents (FCNC) at tree level, and we have introduced the ordinary quark mixing matrices for the model when the first family transforms differently to the other two with respect to $SU(3)_L$. We obtain a huge number of heavy bilepton pairs produced for two different values of the center of mass energy of the LHC.



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