  Direct nuclear reactions with radioactive ion beams represent an extremely
powerful tool to extend the study of fundamental nuclear properties far from
stability. These measurements require pure and dense targets to cope with the
low beam intensities. The $^3$He cryogenic target HeCTOr has been designed to
perform direct nuclear reactions in inverse kinematics. The high density of
$^3$He scattering centers, of the order of 10$^{20}$ atoms/cm$^2$, makes it
particularly suited for experiments where low-intensity radioactive beams are
involved. The target was employed in a first in-beam experiment, where it was
coupled to state-of-the-art gamma-ray and particle detectors. It showed
excellent stability in gas temperature and density over time. Relevant
experimental quantities, such as total target thickness, energy resolution and
gamma-ray absorption, were determined through dedicated Geant4 simulations and
found to be in good agreement with experimental data.
