Related papers: Heavy neutrino mixing prospects at hadron collider…
Majorana and pseudo-Dirac heavy neutrinos are introduced into the type-I and inverse seesaw models, respectively, in explaining the naturally small neutrino mass. TeV scale heavy neutrinos can also be accommodated to have a sizable mixing…
A search for heavy right-handed Majorana neutrinos is performed with the ATLAS detector at the CERN Large Hadron Collider, using the 140 $\mathrm{fb}^{-1}$ of proton-proton collision data at $\sqrt{s}$ = 13 TeV collected during Run 2. This…
The extension of the standard model with new high-scale weakly coupled physics involving right-handed neutrinos in an effective field theory framework (SMNEFT) allows for a systematic study of heavy neutrinos phenomenology in current and…
We study the LHC discovery potential for heavy Majorana neutrino singlets in the process pp -> W+ -> l+ N -> l+ l+ jj (l=e,mu) plus its charge conjugate. With a fast detector simulation we show that backgrounds involving two like-sign…
The Standard Model of particle physics is still lacking an understanding of the generation and nature of neutrino masses. A favorite theoretical scenario (the see-saw mechanism) is that both Dirac and Majorana mass terms are present,…
We investigate the sensitivity of future high-energy muon colliders to heavy Majorana neutrinos, considering both opposite-sign ($\mu^+\mu^-$) and same-sign ($\mu^+\mu^+$) collision modes. We focus on $\mu^+\mu^-$ colliders operating at…
In this study we explore the LHC's Run II potential to the discovery of heavy Majorana neutrinos, with luminosities between $30$ and $3000$ fb$^{-1}$ in the $l^{\pm}l^{\pm}j~j$ final state. Given that there exist many models for neutrino…
Right-handed (RH) Majorana neutrinos play a crucial role in understanding the origin of neutrino mass, the nature of dark matter and the mechanism of matter-antimatter asymmetry. In this work, we investigate the observability of heavy…
This letter reports on a search for hypothetical heavy neutrinos, N, and right-handed gauge bosons, WR, in events with two high transverse momentum leptons and at least one high transverse momentum hadronic jet. The results were obtained…
Results are presented of a search for a heavy Majorana neutrino N$_\ell$ decaying into two same-flavor leptons $\ell$ (electrons or muons) and a quark-pair jet. A model is considered in which the N$_\ell$ is an excited neutrino in a…
In the conventional type-(I+II) seesaw model, the effective mass matrix of three known light neutrinos is given by M_nu = M_L - M_D M^{-1}_R M^T_D in the leading-order approximation. We propose an intriguing scenario, in which the…
We consider the effects of heavy Majorana neutrinos N with sub-TeV masses. We argue that the mere presence of these particles would be a signal of physics beyond the minimal seesaw mechanism and their interactions are, therefore, best…
We consider the production of a heavy neutrino and its possible signals at the Large Hadron-electron Collider (LHeC) in the context of an inverse-seesaw model for neutrino mass generation. The inverse seesaw model extends the Standard Model…
We discuss the future prospects of heavy neutrino searches at next generation lepton colliders. In particular, we focus on the planned electron-positron colliders, operating in two different beam modes, namely, $e^+e^-$ and $e^-e^-$. In the…
The lepton number violating signal of like-sign-dileptons (LSD), p p \to \ell^\pm\ell^\pm + 2 jets, is investigated within a model of mixing in the neutrino sector assuming the existence of heavy Majorana neutrino states with a left--handed…
A search for physics beyond the standard model in the final state with two same-flavour leptons (electrons or muons) and two quarks produced in proton-proton collisions at sqrt(s) = 13 TeV is presented. The data were recorded by the CMS…
A machine learning method is applied to analyze lepton mass matrices numerically. The matrices were obtained within a framework of high scale SUSY and a flavor symmetry, which are too complicated to be solved analytically. In this numerical…
The neutrino masses and flavor mixings, which are missing in the Standard Model (SM), can be naturally incorporated in the type-I seesaw extension of the SM with heavy Majorana neutrinos being singlet under the SM gauge group. If the heavy…
A search for heavy right-handed Majorana or Dirac neutrinos $N_{\mathrm{R}}$ and heavy right-handed gauge bosons $W_{\mathrm{R}}$ is performed in events with energetic electrons or muons, with the same or opposite electric charge, and…
The Majorana nature of neutrinos can be experimentally verified only via {\it lepton-number} violating processes involving charged leptons. We study 36 lepton-number violating ($\lv$) processes from the decays of tau leptons and…