Axino dark matter with R-parity violation and 130 GeV gamma-ray line

Abstract

We show that decaying axino dark matter with R-parity violation can explain the observed excess of the 130 GeV gamma-ray line from the Galactic center in the Fermi data. The branching fraction of the axino decay into monochromatic photons can be O(1), and constraints from continuum gamma-rays and the anti-proton flux are ameliorated. The Pecce–Quinn scale of O(1013–1014) GeV and the R-parity violation parameter of O(10−12–10−11) are cosmologically favored.