Related papers: Heavy neutral fermions at the high-luminosity LHC
We study the neutralino being the Lightest Supersymmetric Particle (LSP) as a cold Dark Matter (DM) candidate with a mass less than 40 GeV in the framework of the Next-to-Minimal-Supersymmetric-Standard-Model (NMSSM). We find that with the…
A search is performed for heavy resonances decaying to two long-lived massive neutral particles, each decaying to leptons. The experimental signature is a distinctive topology consisting of a pair of oppositely charged leptons originating…
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…
All extensions of the standard model that generate Majorana neutrino masses at the electro-weak scale introduce some "heavy" mediators, either fermions and/or scalars, weakly coupled to leptons. Here, by "heavy" we understand implicitly the…
We consider a dark sector containing a pair of almost degenerate states coupled to the Standard Model through a dark photon mediator. This set-up constitutes a simple realization of the inelastic dark matter scenario. The heaviest dark…
Heavy neutral leptons (HNLs) can cause new effective interactions of Standard Model particles, particularly charged lepton flavour violation (cLFV) processes. The non-observation of cLFV processes, therefore, puts constraints on the…
Generic extensions of the Standard Model that respect baryon and lepton numbers have accidentally stable particles. Typical examples are the lightest exotic neutral fermion, or "neutralino", and fields with non-trivial lepton and baryon…
Future neutrino and cosmological experiments will perform powerful searches for new light particles. After a general introduction we discuss how a new light fermion (`sterile neutrino') could manifest.
For years, it has been believed that the main LHC detectors can only restrictively play the role of a lifetime frontier experiment exploring the parameter space of long-lived particles (LLPs) - hypothetical particles with tiny couplings to…
Displaced vertex (DV) signatures at colliders offer a powerful probe of new long-lived particles beyond the Standard Model. Among the best-motivated candidates are heavy neutral leptons (HNLs) - heavier counterparts of Standard Model…
We investigate a neutrino mass model in which the neutrino data is accounted for by bilinear R-parity violating supersymmetry with anomaly mediated supersymmetry breaking. We focus on the CERN Large Hadron Collider (LHC) phenomenology,…
We study the prospects of a displaced-vertex search of sterile neutrinos at the Large Hadron Collider (LHC) in the framework of the neutrino-extended Standard Model Effective Field Theory ($\nu$SMEFT). The production and decay of sterile…
Long-lived particles (LLPs) are a common feature in many beyond the Standard Model theories, including supersymmetry, and are generically produced in exotic Higgs decays. Unfortunately, no existing or proposed search strategy will be able…
Many existing or proposed intensity-frontier search experiments look for decay signatures of light long-lived particles (LLPs), highly displaced from the interaction point, in a distant detector that is well-shielded from SM background.…
We consider two theoretical scenarios, each including a $\mathbb{Z}_{2}$-odd sector and leading to an elementary dark matter candidate. The first one is a variant of the Type-III seesaw model where one lepton triplet is…
Scenarios with new physics particles feebly interacting with the Standard Model sector provide compelling candidates for dark matter searches. Geared with a set of new experiments for the detection of neutrinos and long-lived particles the…
We investigate production and detection prospects of the quintuplet heavy leptons at the LHC in the context of a new model which is proposed as a viable and testable solution to the neutrino masses problem. We classify the signals, carry…
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…
Little Higgs models with T-parity can easily satisfy electroweak precision tests and at the same time give a stable particle which is a candidate for cold dark matter. In addition to little Higgs heavy gauge bosons, this type of models…
A new fixed-target experiment at the CERN SPS accelerator is proposed that will use decays of charm mesons to search for Heavy Neutral Leptons (HNLs), which are right-handed partners of the Standard Model neutrinos. The existence of such…