Pseudo-Majoron as Light Mediator of Singlet Scalar Dark Matter

Abstract

In the singlet-triplet majoron model of neutrino mass, lepton number is spontaneously broken. If it is also softly broken, then a naturally light pseudoscalar particle ${\eta }_I$ exists. It may then act as a light mediator for a real singlet scalar $\chi$ with odd dark parity. It is itself unstable, but decays dominantly to two neutrinos through its triplet scalar component, thereby not disturbing the cosmic microwave background (CMB). It also mixes with the standard-model Higgs boson only in one loop, thereby not contributing significantly to the elastic scattering of $\chi$ off nuclei in dark-matter direct-search experiments.

10 pages

References in corpus (2)

• Strong constraints on self-interacting dark matter with light mediators
• Self-Interacting Dark Matter with Naturally Light Mediator

Cited by in corpus (6)

• Lepton Flavor Violation Induced by Dark Matter
• Type-II Majoron Dark Matter
• Light dark matter in a minimal extension with two additional real singlets
• Connection between $\nu n\to \bar{\nu }\bar{n}$ reactions and $n$-$\bar{n}$ oscillations via additional Higgs triplets
• Explaining the AMS positron excess via Right-handed Neutrinos
• Leptonic Dark Matter with Scalar Dilepton Mediator