  The three-body system inside the unitary window is studied for three equal
bosons and three equal fermions having $1/2$ spin-isospin symmetry. We perform
a gaussian characterization of the window using a gaussian potential to define
trajectories for low-energy quantities as binding energies and phase shifts. On
top of this trajectories experimental values are placed or, when not available,
quantities calculated using realistic potentials that are known to reproduce
experimental values. The intention is to show that the gaussian
characterization of the window, thought as a contact interaction plus range
corrections, captures the main low-energy properties of real systems as for
example three helium atoms or three nucleons. The mapping of real systems on
the gaussian trajectories is taken as indication of universal behavior. The
trajectories continuously link the physical points to the unitary limit
allowing for the explanation of strong correlations between observables
appearing in real systems and which are known to exist in that limit. In the
present study we focus on low-energy bound, scattering and virtual states.
