Minimal Realization of Light Thermal Dark Matter

Area of Science:

• Particle Physics
• Cosmology
• Astrophysics

Background:

• Dark matter (DM) constitutes a significant portion of the universe's mass.
• Sub-GeV thermal relics present challenges for detection and model building.
• Existing models often face constraints from indirect detection experiments.

Purpose of the Study:

• To propose a minimal UV-complete model for sub-GeV dark matter.
• To explore a scenario where dark matter annihilates into standard model leptons.
• To connect dark matter physics with the muon (g-2) anomaly and neutrino oscillations.

Main Methods:

• Utilizing a two-Higgs-doublet model to introduce a light mediator.
• Investigating dark matter annihilation into standard model leptons.
• Embedding the model within the Zee model to incorporate neutrino physics.

Main Results:

• A minimal model for kinematically forbidden, sub-GeV thermal relic dark matter.
• Dark matter annihilation into leptons via a light mediator, evading indirect detection constraints.
• A natural explanation for the muon (g-2) anomaly due to sizable couplings to muons.
• A connection between neutrino oscillations and dark matter relic abundance within the Zee model framework.

Conclusions:

• The proposed model offers a testable framework for sub-GeV dark matter.
• New physics at or below the electroweak scale is predicted.
• The model is amenable to verification at colliders, beam-dump experiments, and gamma-ray telescopes.