Eur. Phys. J. C (2018) 78: 696
https://doi.org/10.1140/epjc/s10052-018-6171-8

Regular Article - Theoretical Physics

Heavy Majorana neutrino pair productions at the LHC in minimal U(1) extended Standard Model

¹ School of Physics, KIAS, Seoul, 02455, Korea
² Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL, 35487, USA

^* e-mail: draut@crimson.ua.edu

Received: 24 January 2018
Accepted: 22 August 2018
Published online: 31 August 2018

Abstract

In our recent paper (Das et al. in Phys Rev D 97:115023, 2018) we explored a prospect of discovering the heavy Majorana right-handed neutrinos (RHNs) at the future LHC in the context of the minimal non-exotic U(1) extended Standard Model (SM), where a pair of RHNs are created via decay of resonantly produced massive U(1) gauge boson (). We have pointed out that this model can yield a significant enhancement of the branching ratio of the boson to a pair of RHNs, which is crucial for discovering the RHNs under the very severe LHC Run-2 constraint from the search for the boson with dilepton final states. In this paper, we perform a general parameter scan to evaluate the maximum production rate of the same-sign dilepton final states (smoking gun signature of Majorana RHNs production) at the LHC, while reproducing the neutrino oscillation data. We also consider the minimal non-exotic U(1) model with an alternative charge assignment. In this case, we find a further enhancement of the branching ratio of the boson to a pair of RHNs compared to the conventional case, which opens up a possibility of discovering the RHNs even before the boson at the future LHC experiment.