Table 1: Properties of the subgroups Upper Scorpius (US), Upper Centaurus Lupus (UCL), and Lower Centaurus Crux (LCC) of Sco OB2, and of our model for Sco OB2. Columns 2-4 list for each subgroup its distance, effective radius, and age. Column 5 lists the median interstellar extinction towards each subgroup. Column 6 lists the number of confirmed Hipparcos members of each subgroup, and is followed by the observed number of singles, binaries, triples, and higher-order systems among the confirmed members in Cols. 7-10, taken from Kouwenhoven et al. (2007). Finally, Cols. 11-13 list the observed multiplicity fraction, non-single star fraction, and companion star fraction among the confirmed members (see Kouwenhoven et al. 2005, for a definition of these fractions). Note that the latter quantities are lower limits due to the presence of unresolved binary and multiple systems. In the bottom row we list the properties of our Sco OB2 model. The number of systems N=S+B (i.e., singles and binaries) used in our model includes substellar objects with masses down to $0.02 ~{M}_\odot$. References: (1) de Zeeuw et al. (1999); (2) de Geus et al. (1989); (3) Preibisch et al. (2002); (4) Mamajek et al. (2002); (5) de Bruijne (1999).
Subgroup D R Age AV $N_\star $ $S_\star$ $B_\star$ $T_\star$ >3 $F_{M,\star}$ $F_{\rm NS,\star}$ $F_{\rm C,\star}$
  pc pc Myr mag                
US 1451 ${\sim} 20^5$ 5-62,3 0.475 1201 64 44 8 3 0.46 0.67 0.61
UCL 1401 ${\sim} 35^5$ 15-224 0.065 2211 132 65 19 4 0.40 0.61 0.52
LCC 1181 ${\sim} 35^5$ 17-234 0.055 1801 112 57 9 1 0.37 0.56 0.44
Model 130 20 5 0.00 9000 varying varying 0 0 varying varying varying

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