On non‐baryonic dark objects in galactic haloes

Taking into account that a hierarchical pattern of clustering appears in cold dark matter scenarios, the existence of cold dark matter substructure in galactic haloes is explored. For this purpose, well‐known dynamical constraints are imposed on non‐baryonic objects, at solar Galactocentric distance. In this paper, aggregates of axions, aggregates of fermions and clusters of these aggregates have been considered, and ranges for their masses and radii have been estimated. Non‐baryonic objects with radii and masses different from those allowed must have been disrupted by dynamical effects, so that their components must be orbiting freely within the Galactic halo. Upper limits for the ratio between the mass (per volume unit) that remains bound to dark objects and the cold dark matter total mass (per volume unit) in the Galactic halo have also been estimated.