Heavy Majorana neutrino pair production from $Z^\prime$ at hadron and lepton colliders

Abstract

A gauged U(1) extension of the Standard Model (SM) is a simple and anomaly free framework where three generations of Majorana type right-handed neutrinos (RHNs) are introduced to generate light neutrino mass and flavor mixings through the seesaw mechanism. We investigate such models at different hadron and lepton colliders via Z induced Majorana type RHNs pair production. We derive bounds on U(1) gauge coupling (g ) comparing the model cross sections with experimentally observed data for different Z mass (M Z ) and RHNs mass (MN ). Using these limits we estimate the allowed RHN pair production cross section which can be manifested by lepton number violating signatures in association with fat-jets at the hadron colliders depending on the mass of the RHNs. Hence we study dilepton and trilepton modes with fat-jet/s of the signal for different benchmark values of M Z and MN . Using fat-jet signatures and studying the signal and corresponding SM backgrounds, we estimate bounds on MN − M Z plane at different center of mass energies which could be probed at different hadron colliders. In the context of the lepton colliders we consider electron positron initial states where Majorana type RHNs can be produced from Z manifesting same sign dilepton plus jets signature and trilepton plus jets in association with missing energy. Studying the signal and corresponding SM backgrounds we estimate the bounds on the MN − M Z plane for different center of mass energies. In the context of U(1) extension of the SM there is an SM singlet BSM scalar which couples with the RHNs. We can probe the Majorana nature of RHNs via this BSM scalar production at electron positron colliders.

Probing heavy Majorana neutrino pair production at ILC in a $U(1)_{\rm B-L}$ extension of the Standard Model

“…Signal events were generated using the WHIZARD event generator 2.8.5 [33]. in [34]. The B-L scenario can be obtained using x H = 0 and x Φ = 1.…”

Constraining the Active-to-Heavy-Neutrino transitional magnetic moments associated with the $Z'$ interactions at FASER$ν$

“…In this work, we consider a scenario of a heavy neutrino N with the presence of a light U (1) gauge boson Z [30][31][32]. The heavy neutrino N can couple to the active neutrinos via a transitional magnetic dipole moment type interaction of the Z boson: N σ µν ν α Z µν , where Z µν is the field strength of the Z boson.…”