  The "in-situ" formation of very wide binaries is hard to explain as their
physical separations are beyond the typical size of a collapsing cloud core
($\approx$5000-10,000 au). Here we investigate the formation process of such
systems. We compute population statistics such as the multiplicity fraction
(MF), companion-star fraction (CSF) and physical separation distribution of
companions in the $\beta$-Pictoris moving group (BPMG). We compare previous
multiplicity studies in younger and older regions and show that the dynamic
evolution of a young population with a high degree of primordial multiplicity
can lead to a processed separation distribution, similar to the field
population. The evolution of outer components is attributed to the dynamical
unfolding of higher-order (triple) systems; a natural consequence of which is
the formation of wide binaries. We find a strong preference for wide systems to
contain three or more components ($>$1000 au: 11 / 14, 10,000 au: 6 / 7). We
argue that the majority of wide binaries identified in young moving groups are
primordial. Under the assumption that stellar populations, within our galaxy,
have statistically similar primordial multiplicity, we can infer that the
paucity of wide binaries in the field is the result of dynamical evolution.

Solar and Stellar Astrophysics