Gamma Lines from the Hidden Sector
  We discuss the visibility of gamma lines from dark matter annihilation. We
point out a class of theories for dark matter which predict the existence of
gamma lines with striking features. In these theories, the final state
radiation processes are highly suppressed and one could distinguish easily the
gamma lines from the continuum spectrum. We discuss the main experimental
bounds and show that one could test the predictions for gamma lines in the near
future in the context of simple gauge theories for dark matter.
