Simplified TeV leptophilic dark matter in light of DAMPE data

Using a simplified framework, we attempt to explain the recent DAMPE cosmic e+ + e− flux excess by leptophilic Dirac fermion dark matter (LDM). The scalar (Φ0) and vector (Φ1) mediator fields connecting LDM and Standard Model particles are discussed. We find that the couplings P ⊗ S, P ⊗ P , V ⊗ A and V ⊗ V can produce the right bump in e+ + e− flux for a DM mass around 1.5 TeV with a natural thermal annihilation cross-section < σv >∼ 3×10−26cm3/s today. Among them, V ⊗V coupling is tightly constrained by PandaX-II data (although LDM-nucleus scattering appears at one-loop level) and the surviving samples appear in the resonant region, mΦ1≃2mχ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {m_{\varPhi}}_{{}_1}\simeq 2{m}_{\chi } $$\end{document}. We also study the related collider signatures, such as dilepton production pp → Φ1 → ℓ+ℓ−, and muon g − 2 anomaly. Finally, we present a possible U(1)X realization for such leptophilic dark matter.