Fermi large area telescope search for photon lines from 30 to 200 GeV and dark matter implications

Abstract

Dark matter (DM) particle annihilation or decay can produce monochromatic γ rays readily distinguishable from astrophysical sources. γ-ray line limits from 30 to 200 GeV obtained from 11 months of Fermi Large Area Space Telescope data from 20-300 GeV are presented using a selection based on requirements for a γ-ray line analysis, and integrated over most of the sky. We obtain γ-ray line flux upper limits in the range 0.6-4.5×10-9cm-2s-1, and give corresponding DM annihilation cross-section and decay lifetime limits. Theoretical implications are briefly discussed. © 2010 The American Physical Society.