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Description
A catalog of common-proper-motion (CPM) companions to stars within 67pc of the Sun is constructed based on the SUPERBLINK proper-motion survey. It contains 1392 CPM pairs with angular separations 30"<{rho}<1800", relative proper motion between the two components less than 25mas/yr, and magnitudes and colors of the secondaries consistent with those of dwarfs in the (M_V_, V-J) diagram. In addition, we list 21 candidate white dwarf CPM companions with separations under 300", about half of which should be physical. We estimate a 0.31 fraction of pairs with red dwarf companions to be physical systems (about 425 objects), while the rest (mostly wide pairs) are chance alignments. For each candidate companion, the probability of a physical association is evaluated. The distribution of projected separations s of the physical pairs between 2kAU and 64kAU follows f(s){prop.to}s^-1.5^, which decreases faster than Opik's law. We find that solar-mass dwarfs have no less than 4.4%+/-0.3% companions with separations larger than 2kAU, or 3.8%+/-0.3% per decade of orbital separation in the 2-16kAU range. The distribution of mass ratio of those wide companions is approximately uniform in the 0.1<q<1.0 range, although we observe a dip at q=~0.5 which, if confirmed, could be evidence of bimodal distribution of companion masses. New physical CPM companions to two exoplanet host stars are discovered.
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