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arXiv · 1411.6866

Constraints on a seesaw model leading to quasidegenerate neutrinos and signatures at the LHC

Gulab Bambhaniya·Subrata Khan·Partha Konar·Tanmoy Mondal
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Abstract

We consider a variant of TeV scale seesaw models in which three additional heavy right handed neutrinos are added to the standard model to generate the quasi-degenerate light neutrinos. This model is theoretically interesting since it can be fully rebuilt from the experimental data of neutrino oscillations except for an unknown factor in the Dirac Yukawa coupling. We study the constrains on this coupling coming from meta-stability of electro-weak vacuum. Even stronger bound comes from the lepton flavor violating decays on this model, especially in a heavy neutrino mass scenario which is within the collider reach. Bestowed with these constrained parameters, we explore the production and discovery potential coming from these heavy neutrinos at the $14$~TeV run of Large Hadron Collider. Signatures with tri-lepton final state together with backgrounds are considered in a realistic simulation.

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Gulab Bambhaniya, Subrata Khan, Partha Konar, Tanmoy Mondal. 2015-05-12. Constraints on a seesaw model leading to quasidegenerate neutrinos and signatures at the LHC. https://doi.org/10.1103/physrevd.91.095007

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