We present a detailed study of the effect of internal bremsstrahlung photons
in the context of the minimal supersymmetric standard models and their impact
on gamma-ray dark matter annihilation searches. We find that although this
effect has to be included for the correct evaluation of fluxes of high energy
photons from neutralino annihilation, its contribution is relevant only in
models and at energies where the lines contribution is dominant over the
secondary photons. Therefore, we find that the most optimistic supersymmetric
scenarios for dark matter detection do not change significantly when including
the internal bremsstrahlung. As an example, we review the gamma-ray dark matter
detection prospects of the Draco dwarf spheroidal galaxy for the MAGIC
stereoscopic system and the CTA project. Though the flux of high energy photons
is enhanced by an order of magnitude in some regions of the parameter space,
the expected fluxes are still much below the sensitivity of the instruments.Comment: 5 pages, twocolumn format, 3 figures:3 references added, accepted as
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