Fermi 130 GeV gamma-ray excess and dark matter annihilation in sub-haloes and in the Galactic centre

Abstract

We analyze publicly available Fermi-LAT high-energy gamma-ray data and confirm the existence of clear spectral feature peaked at E=130GeV. Scanning over the Galaxy we identify several disconnected regions where the observed excess originates from. Our best optimized fit is obtained for the central region of Galaxy with a clear peak at 130GeV with local statistical significance 4.5 sigma. The observed excess is not correlated with Fermi bubbles. We compute the photon spectra induced by dark matter annihilations into two and four standard model particles, the latter via two light intermediate states, and fit the spectra with data. Since our fits indicate sharper and higher signal peak than in the previous works, data favors dark matter direct two-body annihilation channels into photons or other channels giving only line-like spectra. If Einasto halo profile correctly predicts the central cusp of Galaxy, dark matter annihilation cross-section to two photons is of order ten percent of the standard thermal freeze-out cross-section. The large dark matter two-body annihilation cross-section to photons may signal a new resonance that should be searched for at the CERN LHC experiments.

Addendum included on the double peak structure of the excess seen due to new improved Fermi-LAT energy resolution

References in corpus (8)

• A Theory of Dark Matter
• Giant Gamma-ray Bubbles from Fermi-LAT: AGN Activity or Bipolar Galactic Wind?
• A Tentative Gamma-Ray Line from Dark Matter Annihilation at the Fermi Large Area Telescope
• Significant Gamma Lines from Inert Higgs Dark Matter
• Gamma Ray Line Constraints on Effective Theories of Dark Matter
• Singlet Scalar Dark Matter: monochromatic gamma rays and metastable vacua
• Indirect detection of light neutralino dark matter in the NMSSM
• Gamma-ray Lines in the Fermi Data: is it a Bubble?

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