Exciting dark matter in the galactic center

Abstract

We reconsider the proposal of excited dark matter (DM) as an explanation for excess 511 keV gamma rays from positrons in the galactic center. We quantitatively compute the cross section for DM annihilation to nearby excited states, mediated by exchange of a new light gauge boson with off-diagonal couplings to the DM states. In models where both excited states must be heavy enough to decay into e^+ e^- and the ground state, the predicted rate of positron production is never large enough to agree with observations, unless one makes extreme assumptions about the local circular velocity in the Milky Way, or alternatively if there exists a metastable population of DM states which can be excited through a mass gap of less than 650 keV, before decaying into electrons and positrons.

Dedicated to the memory of Lev Kofman; 16 pages, 9 figures; v3 added refs, minor changes, accepted to PRD

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Cited by in corpus (22)

• Cores in Dwarf Galaxies from Dark Matter with a Yukawa Potential
• Self-Scattering for Dark Matter with an Excited State
• An X-Ray Line from eXciting Dark Matter
• Consistent Scenarios for Cosmic-Ray Excesses from Sommerfeld-Enhanced Dark Matter Annihilation
• Ruling out the light WIMP explanation of the galactic 511 keV line
• Interacting dark matter contribution to the Galactic 511 keV gamma ray emission: constraining the morphology with INTEGRAL/SPI observations
• Can multistate dark matter annihilation explain the high-energy cosmic ray lepton anomalies?
• Excluding the Light Dark Matter Window of a 331 Model Using LHC and Direct Dark Matter Detection Data
• Metastable dark matter mechanisms for INTEGRAL 511 keV $\gamma$ rays and DAMA/CoGeNT events
• Searching for Decaying and Annihilating Dark Matter with Line Intensity Mapping
• Nonabelian dark matter models for 3.5 keV X-rays
• p-wave Annihilating Dark Matter from a Decaying Predecessor and the Galactic Center Excess
• Cosmic Microwave Background Constraints on Dark Matter Models of the Galactic Center 511 keV Signal
• Multi-messenger constraints on dark matter annihilation into electron-positron pairs
• The Morphology of Exciting Dark Matter and the Galactic 511 keV Signal
• Abelian dark matter models for 511 keV gamma rays and direct detection
• MiXDM: Cosmic Ray Signals from Multiple States of Dark Matter
• Low Energy INTEGRAL Positrons from eXciting Dark Matter
• Magnetized matter effects on dilaton photon mixing
• Excited Dark Matter versus PAMELA/Fermi
• Reviving MeV-GeV Indirect Detection with Inelastic Dark Matter
• Updated Constraints on the Injection Energy of Positrons Generating the Galactic 511 keV $\gamma$-ray line