The quest for indirect dark matter detection: a critical outlook

Piero Ullio, SISSA (Trieste)

The dark matter puzzle is one of deepest and longest-standing problems in Science. While there is overwhelming evidence that dark matter is the building block of all structures in the Universe, its nature remains unknown.

There are several theoretical frameworks predicting that dark matter halos - including the halo of our own galaxy - are made of particles which can annihilate in pairs or decay into ordinary Standard Model states, giving rise to exotic astrophysical signals.

The focus in recent years has been in particular on the search for exotic components with gamma- and cosmic-ray observatories, with a dramatic improvement in quality and coverage of the available data. 

Unfortunately, for none of the originally proposed targets a dark matter signal stands clearly above backgrounds from standard astrophysical sources: it is then apparent that to keep exploiting these channels as efficient tools to either discover dark matter or set constraints on dark matter candidates, a closer addressing of signals and backgrounds are needed. 

We illustrate this point for two targets, the Galactic center and dwarfs satellites which most recently have been highlighted, respectively, as most promising for a tentative detection and most constraining on particle dark matter models.