To address the statistics of binary stars in the 8-Myr old Upper Scorpius star formation region , we conducted speckle-interferometric survey of 614 association members more massive than 0.4 { \cal M } _ { \odot } ( spectral types earlier than M3V ) based on the list of Luhman et al .
( 2018 ) .
We resolved 187 pairs , 55 of those are new discoveries .
Using also the published data and the Gaia DR2 , a catalog of 250 physical binaries is produced .
We carefully estimated detection limits for each target and studied binary statistics in the separation range from 0 \farcs 06 to 20″ ( 9 to 2800 au ) , as well as clustering at larger separations .
The frequency of companions with mass ratios q > 0.3 in this separation range is 0.33 \pm 0.04 and 0.35 \pm 0.04 for early M and solar-type stars , respectively , larger by 1.62 \pm 0.22 and 1.39 \pm 0.18 times compared to field stars of similar masses .
The excess is produced mostly by pairs closer than 100 au .
At separations from 100 to 10 ^ { 4 } au , the separation distribution and companion fraction resemble those of solar-type stars in the field .
However , unlike in the field , we see a relative deficit of equal-mass binaries at separations of \sim 500 au , compared to smaller and larger separations .
The distribution of q depends on the separation , with a preference of larger q and a larger fraction of twins with q > 0.95 at smaller separations .
The binary population of Upper Scorpius differs from binaries in the field in several ways and suggests that binary statistics is not universal .