Dark matter searches with Cherenkov telescopes: nearby dwarf galaxies or
  local galaxy clusters?
  In this paper, we compare dwarf galaxies and galaxy clusters in order to
elucidate which object class is the best target for gamma-ray DM searches with
imaging atmospheric Cherenkov telescopes (IACTs). We have built a mixed
dwarfs+clusters sample containing some of the most promising nearby dwarf
galaxies (Draco, Ursa Minor, Wilman 1 and Segue 1) and local galaxy clusters
(Perseus, Coma, Ophiuchus, Virgo, Fornax, NGC5813 and NGC5846), and then
compute their DM annihilation flux profiles by making use of the latest
modeling of their DM density profiles. We also include in our calculations the
effect of DM substructure. Willman 1 appears as the best candidate in the
sample. However, its mass modeling is still rather uncertain, so probably other
candidates with less uncertainties and quite similar fluxes, namely Ursa Minor
and Segue 1, might be better options. As for galaxy clusters, Virgo represents
the one with the highest flux. However, its large spatial extension can be a
serious handicap for IACT observations and posterior data analysis. Yet, other
local galaxy cluster candidates with more moderate emission regions, such as
Perseus, may represent good alternatives. After comparing dwarfs and clusters,
we found that the former exhibit annihilation flux profiles that, at the
center, are roughly one order of magnitude higher than those of clusters,
although galaxy clusters can yield similar, or even higher, integrated fluxes
for the whole object once substructure is taken into account. Even when any of
these objects are strictly point-like according to the properties of their
annihilation signals, we conclude that dwarf galaxies are best suited for
observational strategies based on the search of point-like sources, while
galaxy clusters represent best targets for analyses that can deal with rather
extended emissions. Finally, we study the detection prospects for IACTs
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