On the offset of the DM cusp and the interpretation of the 130 GeV line   as a DM signal
  We show that the cusp in the dark matter (DM) distribution required to explain the recently found excess in the gamma-ray spectrum at energies ~130 GeV in terms of the DM annihilations cannot survive the tidal forces if it is offset by ~1.5^\circ from the Galactic centre as suggested by observations. 
Dmitry Gorbunov, Peter Tinyakov
astro-ph.CO astro-ph.GA hep-ph