Related papers: Heavy Neutral Leptons at Muon Colliders
We explore the potential to use machine learning methods to search for heavy neutrinos, from their hadronic final states including a fat-jet signal, via the processes $pp \rightarrow W^{\pm *}\rightarrow \mu^{\pm} N \rightarrow \mu^{\pm}…
We report a search for a heavy neutral lepton (HNL) that mixes predominantly with $\nu_\tau$. The search utilizes data collected with the Belle detector at the KEKB asymmetric energy $e^+ e^-$ collider. The data sample was collected at and…
A future multi-TeV muon collider would provide an important probe for Majorana neutrinos. A muon collider with a collision energy of $\sim$30 TeV would be sensitive to $\nu_e-\nu_\mu$ transition dipole moments of the order of $\sim…
A feasibility study is performed for searching vector-like leptons at a muon collider, in the context of the "4321 model", an ultraviolet-complete model with rich collider phenomenology together with potential to explain recent existing…
A search for neutral heavy leptons (NHLs) has been performed using an instrumented decay channel at the NuTeV (E-815) experiment at Fermilab. The decay channel was composed of helium bags interspersed with drift chambers, and was used in…
Flavor-breaking interactions due to heavy new physics can be probed at a 10 TeV muon collider in the high-energy production of quarks and leptons. The high collision energy mitigates the suppression of the new interactions, offering…
This paper investigates the $e^-e^+\to Zh_1$ sensitivity for Higgs boson's rare decay into heavy neutrinos $h_1 \to NN$ at the proposed electron-positron collider, with the focus on multi-lepton final states that contain same-sign lepton…
Two recent searches for heavy neutral leptons (HNLs) performed with proton-proton collision data recorded at 13 TeV by the CMS experiment are presented. A prompt search in the trilepton final state analyses events with exactly three charged…
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…
Majorana properties of neutrinos have long been a focus in the pursuit of possible new physics beyond the standard model, which has motivated lots of dedicated theoretical and experimental studies. A future same-sign muon collider is an…
We study the phenomenology of heavy neutral leptons (HNLs) at the LHC in effective field theory, concentrating on $d=6$ operators with top quarks. Depending on the operator choice and HNL mass, the HNLs will be produced either from…
A high energy muon collider can provide new and complementary discovery potential to the LHC or future hadron colliders. Leptoquarks are a motivated class of exotic new physics models, with distinct production channels at hadron and lepton…
In this paper, we study the potential of future colliders to explore the parameter space of heavy neutral leptons (HNLs) through the dipole portal. We consider hadron colliders such as the LHC in the high luminosity phase and FCC-hh, and…
Heavy neutral leptons $N$ are introduced to explain the tiny neutrino masses via the seesaw mechanism. For proper small mixing parameter $V_{\ell N}$, the heavy neutral leptons $N$ become long-lived, which leads to the displaced vertex…
Heavy neutral leptons (HNLs) are hypothetical particles proposed as a potential explanation for neutrino oscillations and the generation of the baryon asymmetry in the Universe. This paper focuses on HNLs with masses significantly above the…
New heavy Majorana and Dirac neutrinos production at future electron-muon colliders are investigated. The production of a single heavy neutrino is shown to be more relevant than pair production when comparing cross sections and neutrino…
New Physics models in which the Standard Model particle content is enlarged via the addition of sterile fermions remain among the most minimal and yet most appealing constructions, particularly since these states are present as building…
A search for a long-lived, heavy neutral lepton ($\mathcal{N}$) in 139 fb$^{-1}$ of $\sqrt{s}=13$ TeV $pp$ collision data collected by the ATLAS detector at the Large Hadron Collider is reported. The $\mathcal{N}$ is produced via $W…
With no concrete evidence for non-gravitational interactions of dark matter to date, it is natural to wonder whether dark matter couples predominantly to the Standard Model (SM)'s neutrinos. Neutrino interactions (and the possible existence…
Next generation neutrino oscillation experiments like DUNE and T2HK are multi-purpose observatories, with a rich physics program beyond oscillation measurements. A special role is played by their near detector facilities, which are…