Testing Type II Radiative Seesaw Model: from Dark Matter Detection to LHC Signatures

TL;DR

This paper investigates the testability of the type II radiative seesaw model linking neutrino mass and dark matter, analyzing detection constraints and collider signatures at the LHC to identify promising experimental signals.

Contribution

It provides a comprehensive analysis of dark matter regions and collider signatures, proposing benchmark points for testing the model at the LHC with detailed simulations.

Findings

Three viable dark matter mass regions identified under current constraints.

Tri-lepton signatures at the LHC can achieve 5σ significance with 100/fb.

Both four-lepton and tri-lepton signals are promising for model testing.

Abstract

We analyse the testability of the type II radiative seesaw in which neutrino mass and dark matter (DM) are related at one-loop level. Under the constraints from DM relic density, direct and indirect detection, and invisible Higgs decays, we find three possible regions of DM mass $M_{s_1}$ that can survive the present and even the future experiments: (1) the Higgs resonance region with $M_{s_1}\sim M_h/2$, (2) the Higgs region with $M_{s_1}\sim M_h$, and (3) the coannihilation region with $M_{s_2}\sim M_{s_1}$. Here $s_{1,2}$ are two scalar singlets with the lighter $s_1$ being the DM candidate. Based on DM properties and direct collider constraints, we choose three benchmark points to illustrate the testability of this model at LHC. We perform a detailed simulation of the four-lepton and tri-lepton signatures at 13 (14) TeV LHC. While both signatures are found to be promising at all benchmark points, the tri-lepton one is even better: it is possible to reach the $5\sigma$ significance with an integrated luminosity of 100/fb.