Neutrino masses and dark matter (DM) might have a common origin. The $\textit{scotogenic}$ model can be considered the proto-type model realizing this idea, but many other variants exist. In this paper we explore the phenomemology of a particular DM neutrino mass model, containing a triplet scalar. We calculate the relic density and check for constraints from direct detection experiments. The parameter space of the model, allowed by these constraints, contains typically a long-lived or quasi-stable doubly charged scalar, that can be searched for at the LHC. We reinterpret existing searches to derive limits on the masses of the scalars of the model and estimate future sensitivities in the high-luminosity phase of the LHC. The searches we discuss can serve to constrain also many other 1-loop neutrino mass models.

Chile

Carolina Arbeláez

Giovanna Cottin

Juan Helo

Spain

Martin Hirsch

Téssio Melo

Long-lived particle phenomenology in one-loop neutrino mass models with dark matter

Brazil

Laura Duarte

Victor Gonçalves

Poland

Daniel Martins

Erratum: Single charged Higgs pair production in exclusive processes at the LHC

The production of a single charged Higgs boson pair by photon–photon interactions in pp collisions at the LHC is investigated in this exploratory study. We focus on the exclusive production, which is characterized by intact protons and two-rapidity gaps in the final state, and assume the type-I two-Higgs-doublet model, which still allows a light charged Higgs. Assuming the leptonic  $$H^{\pm }\rightarrow [\tau \nu _{\tau }]$$  <math> <mrow> <msup> <mi>H</mi> <mo>±</mo> </msup> <mo>→</mo> <mrow> <mo>[</mo> <mi>τ</mi> <msub> <mi>ν</mi> <mi>τ</mi> </msub> <mo>]</mo> </mrow> </mrow> </math>   decay mode, we derive predictions for the transverse momentum, rapidity and invariant mass distributions of the  $$\tau ^+ \tau ^-$$  <math> <mrow> <msup> <mi>τ</mi> <mo>+</mo> </msup> <msup> <mi>τ</mi> <mo>-</mo> </msup> </mrow> </math>   pair for different values of the charged Higgs mass. The contributions of different background processes are also estimated. Our results indicate that the contribution of the exclusive  $$H^+ H^-$$  <math> <mrow> <msup> <mi>H</mi> <mo>+</mo> </msup> <msup> <mi>H</mi> <mo>-</mo> </msup> </mrow> </math>   production for the  $$[\tau ^{+}\nu _{\tau }][\tau ^{-} \nu _{\tau }]$$  <math> <mrow> <mrow> <mo>[</mo> <msup> <mi>τ</mi> <mo>+</mo> </msup> <msub> <mi>ν</mi> <mi>τ</mi> </msub> <mo>]</mo> </mrow> <mrow> <mo>[</mo> <msup> <mi>τ</mi> <mo>-</mo> </msup> <msub> <mi>ν</mi> <mi>τ</mi> </msub> <mo>]</mo> </mrow> </mrow> </math>   final state is non-negligible and can, in principle, be used to searching for a light charged Higgs.

Single charged Higgs pair production in exclusive processes at the LHC

We propose a class of models providing an explanation of the origin of light neutrino masses, the baryon asymmetry of the Universe via leptogenesis and offering viable dark matter candidates. In these models the Majorana masses of the active neutrino are generated by the inverse seesaw mechanism with the lepton number violating right-handed Majorana neutrino masses μ arising at three loops. The latter is ensured by the preserved discrete symmetries, which also guarantee the stability of the dark matter candidate. We focus on one of these models and perform a detailed analysis of the phenomenology of its leptonic sector. The model can successfully accommodate baryogenesis through leptogenesis in both weak and strong washout regimes. The lightest heavy fermion turns out to be a viable dark matter candidate, provided that the entries of the Majorana submatrix μ are in the keV to MeV range. The solutions are consistent with the experimental constraints, accommodating both mass orderings for active neutrinos, in particular charged-lepton flavor violating decays μ → eγ, μ → eee, and the electron-muon conversion processes get sizable rates within future sensitivity reach.

France

Asmaa Abada

United Arab Emirates

Nicolás Bernal

A. Cárcamo Hernández

Sergey Kovalenko

Three-loop inverse scotogenic seesaw models

We propose a scotogenic model for generating neutrino masses through a three-loop seesaw. It is a minimally extended inert doublet model with a spontaneously broken global symmetry U(1)′ and a preserved ℤ2 symmetry. The three-loop suppression allows the new particles to have masses at the TeV scale without fine-tuning the Yukawa couplings. The model leads to a rich phenomenology while satisfying all the current constraints imposed by neutrinoless double-beta decay, charged-lepton flavor violation, and electroweak precision observables. The relatively large Yukawa couplings lead to sizable rates for charged lepton flavor violation processes, well within future experimental reach. The model could also successfully explain the W mass anomaly and provides viable fermionic or scalar dark matter candidates.

Antonio Cárcamo Hernández

Japan

Takashi Toma

Phenomenological and cosmological implications of a scotogenic three-loop neutrino mass model

General Two Higgs Doublet Models (2HDM) are popular Standard Model extensions but feature flavor changing interactions and lack neutrino masses. We discuss a 2HDM where neutrino masses are generated via type I seesaw and propose an extension where neutrino masses are generated via a type II seesaw mechanism with flavor changing interactions being absent via the presence of a U(1) gauge symmetry. After considering a variety of bounds such as those rising from collider and electroweak precision we show that our proposal stands as a UV complete 2HDM with a dark photon where neutrino masses and flavor changing interactions are addressed. A possible dark matter realization is also discussed.

Daniel Camargo

Alex Dias

Farinaldo Queiroz

Neutrino masses in a two Higgs doublet model with a U(1) gauge symmetry