Related papers: Heavy neutrino mixing prospects at hadron collider…
We discuss the process $\ell^+\ell^- \to N W^{\pm} \ell^{\mp}$, where $N$ is a heavy Majorana neutrino and $\ell = e, \mu$. Large cross sections are expected for these processes at high center-of-mass energies, which can be reached at…
We study the neutrino mixing matrix (the MNS matrix) in the seesaw model. By assuming a large mass hierarchy for the heavy right-handed Majorana mass, we show that, in the diagonal Majorana base, the MNS matrix is determined by a unitary…
In the inverse see-saw model the effective neutrino Yukawa couplings can be sizable due to a large mixing angle between the light $(\nu)$and heavy neutrinos $(N)$. When the right handed neutrino $(N)$ can be lighter than the Standard Model…
The future high-energy muon colliders, featuring both high energy and low background, could play a critical role in our searches for new physics. The smallness of neutrino mass is a puzzle of particle physics. Broad classes of solutions to…
Possibilities for detecting heavy Majorana neutrinos ($N$'s) at future $e{\mu}$ colliders are investigated. In contrast to the $e^-e^+$ colliders (LEP200 and NLC), the center-of-mass (CMS) energies achieved at $e{\mu}$ colliders can be much…
We discuss the possibility of observing multi-lepton signals at the Large Hadron Collider (LHC) from the production and decay of heavy Standard Model (SM) singlet neutrinos added in extensions of SM to explain the observed light neutrino…
We study the single production of heavy neutrinos via the processes $e^-e^+ \to \nu N$ and $e^-\gamma \to W^- N$ at future linear colliders. As a base of our considerations we take a wide class of models, both with vanishing and…
We study a multi-localization model for charged leptons and neutrinos, including the possibility of a see-saw mechanism. This framework offers the opportunity to allow for realistic solutions in a consistent model without fine-tuning of…
The Standard Model (SM) describes particle physics with great precision. However, it does not account for the generation of neutrino masses, whose nature we do not understand. Both a Dirac and a Majorana mass term could intervene, leading…
A search for a heavy neutral lepton N of Majorana nature decaying into a W boson and a charged lepton is performed using the CMS detector at the LHC. The targeted signature consists of three prompt charged leptons in any flavor combination…
We discuss the prospects of studying lepton number violating processes in order to identify Majorana neutrinos from low scale seesaw mechanisms at lepton-proton colliders. In particular, we consider the scenarios of colliding electrons with…
We study the production of heavy neutrinos at the Large Hadron Collider (LHC) through the dominant s-channel production mode as well as the vector boson fusion (VBF) process. We consider the TeV scale minimal linear seesaw model containing…
In the type-I seesaw model the size of mixing between light and heavy neutrinos, nu and N, respectively, is of order the square root of their mass ratio, (m_nu/m_N)^(1/2), with only one generation of the neutrinos. Since the light-neutrino…
We investigate the possibility of detecting Majorana neutrinos at the Large Hadron-electron Collider (LHeC), an electron-proton collision mode at CERN. We study the $l_j^{+} + 3 jets$ ($l_j\equiv e ,\mu ,\tau$) final states which are, due…
Majorana neutrinos in the seesaw model can have sizable mixings through which they can be produced at the Large Hadron Collider (LHC) and show a remarkable Lepton Number Violating (LNV) signature. In this article we study the LNV decay of…
We investigate TeV scale seesaw scenarios at $\mu^+ e^-$ and $\mu^+ \mu^+$ colliders in the $\mu$TRISTAN experiment. In minimal type-I seesaw scenario we consider two generations of Standard Model (SM) singlet heavy Majorana type Right…
We utilize the lepton number violation signal process $p\, e^- \to \tau^+ jjj$ to search for heavy Majorana neutrinos at future proton-electron colliders. The LHeC (FCC-eh) is considered to run with an electron beam energy of 60 GeV, a…
We study the collider signature of pseudo-Dirac heavy neutrinos in the inverse seesaw scenario, where the heavy neutrinos with mass at the electroweak scale can have sizable mixings with the Standard Model neutrinos, while providing the…
A search for heavy right-handed Majorana or Dirac neutrinos $N_R$ and heavy right-handed gauge bosons $W_R$ is performed in events with a pair of energetic electrons or muons, with the same or opposite electric charge, and two energetic…
We study the discovery potential for detecting new neutral heavy Majorana leptons as suggested by some extentions of the Standard Model in recently proposed electron-proton colliders. Since 1998-1999 the option of an electron-proton…