Enhancement of Dark Matter Annihilation via Breit-Wigner Resonance

Abstract

The Breit-Wigner enhancement of the thermally averaged annihilation cross section <σv> is shown to provide a large boost factor when the dark matter annihilation process nears a narrow resonance. We explicitly demonstrate the evolution behavior of the Breit-Wigner enhanced <σv> as the function of universe temperature for both the physical and unphysical pole cases. It is found that both of the cases can lead an enough large boost factor to explain the recent PAMELA, ATIC and PPB-BETS anomalies. We also calculate the coupling of annihilation process, which is useful for an appropriate model building to give the desired dark matter relic density.

4 pages, 4 figures, references added, accepted for publication in Physical Review D

References in corpus (6)

• A Theory of Dark Matter
• Cosmology and Astrophysics of Minimal Dark Matter
• A new measurement of the antiproton-to-proton flux ratio up to 100 GeV in the cosmic radiation
• PAMELA data and leptonically decaying dark matter
• Gamma rays and positrons from a decaying hidden gauge boson
• The Dark Matter Constraints on the Left-Right Symmetric Model with Z_2 Symmetry

Cited by in corpus (6)

• Inverse Compton constraints on the Dark Matter e+e- excesses
• Phenomenology of Dark Matter annihilation into a long-lived intermediate state
• Double Type-II Seesaw, Baryon Asymmetry and Dark Matter for Cosmic e^\pm Excesses
• Type II Seesaw and the PAMELA/ATIC Signals
• Constraints on Dark Matter Annihilation Cross Section in Scenarios of Brane-World and Quintessence
• Enhanced Dark Matter Annihilation Rate for Positron and Electron Excesses from Q-ball Decay