Scalar dark matter, type II seesaw and the DAMPE cosmic ray e++e− excess

Abstract

The DArk Matter Particle Explorer (DAMPE) has reported a measurement of the flux of high energy cosmic ray electrons plus positrons (CREs) in the energy range between 25 GeV and 4.6 TeV. With unprecedented high energy resolution, the DAMPE data exhibit an excess of the CREs flux at an energy of around 1.4 TeV. In this letter, we discuss how the observed excess can be understood in a minimal framework where the Standard Model (SM) is supplemented by a stable SM singlet scalar as dark matter (DM) and type II seesaw for generating the neutrino mass matrix. In our framework, a pair of DM particles annihilates into a pair of the SM SU(2) triplet scalars (∆s) in type II seesaw, and the subsequent ∆ decays create the primary source of the excessive CREs around 1.4 TeV. The lepton flavor structure of the primary source of CREs has a direct relation with the neutrino oscillation data. We find that the DM interpretation of the DAMPE excess determines the pattern of neutrino mass spectrum to be the inverted hierarchy type, taking into account the constraints from the Fermi-LAT observations of dwarf spheroidal galaxies.

Explaining the DAMPE e+e− excess using the Higgs triplet model with a vector dark matter

“…Hence, the model can readily evade the constraints from direct searches. Note added.-After finishing this work, a similar analysis also appeared [39]. In that work, the authors also employ leptonic decays of the Higgs triplet fields to explain the DAMPE e þ e − excess but has a scalar dark matter candidate.…”

Scalar dark matter explanation of the DAMPE data in the minimal left-right symmetric model

“…Some models are based on the typical new-gauge anomaly-free Uð1Þ family symmetry with the corresponding gauge boson as the mediator [65][66][67][68][69][70][71]. Other proposals, such as a scalar mediator with typical lepton-specific Yukawa couplings, have also been discussed [83][84][85][86][87][88][89]. However, many existing DM explanations of the DAMPE results are rather ad hoc and the involved interactions are not naturally the consequence of a well-motivated popular beyond-the-SM (BSM) model.…”

Prospects of type-II seesaw models at future colliders in light of the DAMPEe+e−excess

“…(12). Given this term, the SM Higgs mediates the spin independent scattering of DM off the nuclei in direct detection experiments, with the cross section [25] …”

“…Note that the annihilation process here is even simpler than in Refs. [25,30,43], where the authors considered also the annihilation of DM into the neutral and singly charged scalars from the triplet. The decay of these scalars gives rise to the TeV scale, almost monochromatic neutrinos, which might be constrained by the IceCube data [34,44].…”

“…[25,30], in this work, we concentrate more on the phenomenological implication of the existence of a 3 TeV DM in the type-II seesaw model, and the prospects and testability at future lepton such as ILC [45] and CLIC [46] and the 100 TeV hadron colliders like FCC-hh [47,48] and SPPC [49]. By interacting with the SM Higgs, all the triplet components can be pair produced in the scalar portal.…”