Indirect searches of dark matter
  If dark matter decays or annihilates into electrons and positrons, it can
affect radiation and cosmic-ray backgrounds. We review a novel, more general
analysis of constraints on decaying dark matter models, by introducing the
response functions based on the current radio, gamma-ray and positron
observations. Constraints can be simply obtained by requiring the convolution
of the response functions with actual decay spectrum of electrons and positrons
smaller than the product of decay lifetime in 10^{26}s and mass in 100GeV. The
response functions just depend on the astrophysical inputs such as the
propagation model, but not on the microscopic decay scenario. Moreover, an
anisotropy analysis of the full-sky radio emissions to identify the
extragalactic dark matter annihilation is shown. We discuss the angular power
spectra of the cosmological synchrotron emission from dark matter annihilations
into electron positron pairs and compare them with astrophysical backgrounds
and Galactic foregrounds. We find that the angular power spectrum of radio
fluxes at around GHz frequencies and in the range of 200 <l <3000 opens a
optimal window to disentangle the dark matter signals from common astrophysical
backgrounds.
