Dark matter annihilation into leptons through gravity portals

• Published in: The journal of high energy physics Vol. 2021; no. 4; pp. 1 - 24
• Main Authors: Sun, Xudong, Dai, Ben-Zhong
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.04.2021; Springer Nature B.V; SpringerOpen
• Subjects: Antiparticles; Antiprotons; Beyond Standard Model; Big Bang theory; Classical and Quantum Gravitation; Cosmic microwave background; Cosmic rays; Cosmology of Theories beyond the SM; Dark matter; Elementary Particles; Field theory; High energy physics; Leptons; Operators; Physics; Physics and Astronomy; Quantum Field Theories; Quantum Field Theory; Quantum Physics; Regular Article - Theoretical Physics; Relativity; Relativity Theory; Scalars; Space telescopes; Standard model (particle physics); String Theory; Beyond Standard Model; Cosmology of Theories beyond the SM
• ISSN: 1029-8479; 1029-8479
• DOI: 10.1007/JHEP04(2021)108

A bstract Dark matter (DM) constitutes 85% of the matter in the Universe. However, its specific particle property is still unclear. The fundamentals of DM particles subject to gravitational interaction, and that the lepton excess in cosmic rays may originate from DM particles, inspired us to investigate DM particle properties beyond the standard model. We assume that a leptophilic SU(2) doublet exists in nature as the mediator connecting DM with visible leptons. Since general relativity is not renormalizable at the quantum level, it should be regarded as an effective field theory’s leading order term. One species of the next-to-leading-order term should be operators linear to the Ricci scalar and containing scalar fields, such as the Higgs field, scalar DM, or the newly introduced SU(2) scalar doublet. These operators can cause DM annihilation through gravity portals. We analyzed constraints from the cosmic antiproton flux, DM relic abundance, cosmic positron flux, cosmic microwave background, and direct detection experiments. The result shows that there is a vast parameter space that is compatible with current experiments. DM with a mass of electroweak scale is only allowed to annihilate into leptons. We further show that the purely gravitational DM better explains the DArk Matter Particle Explorer cosmic lepton excess. Our work provides a promising mechanism for DM particles to connect with standard model particles.