We describe an astrometric and spectroscopic campaign to confirm the youth and association of a complete sample of candidate wide companions in Taurus and Upper Sco .
Our survey found fifteen new binary systems ( 3 in Taurus and 12 in Upper Sco ) with separations of 3-30″ ( 500-5000 AU ) among all of the known members with masses of 2.5-0.012 M _ { \sun } .
The total sample of 49 wide systems in these two regions conforms to only some expectations from field multiplicity surveys .
Higher-mass stars have a higher frequency of wide binary companions , and there is a marked paucity of wide binary systems near the substellar regime .
However , the separation distribution appears to be log-flat , rather than declining as in the field , and the mass ratio distribution is more biased toward similar-mass companions than the IMF or the field G dwarf distribution .
The maximum separation also shows no evidence of a limit at \lesssim 5000 AU until the abrupt cessation of any wide binary formation at system masses of \sim 0.3 M _ { \sun } .
We attribute this result to the post-natal dynamical sculpting that occurs for most field systems ; our binary systems will escape to the field intact , but most field stars are formed in denser clusters and do not .
In summary , only wide binary systems with total masses \lesssim 0.3 M _ { \sun } appear to be “ unusually wide ” .