The distribution of visual binaries with two bright components
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Among the 4908 stellar systems which have at least one resolvable component brighter than V = 6.00 are 115 systems with two or more resolvable components both brighter than V = 6.00. These bright stellar systems, both single and double, are modeled by a distribution convolving (1) formulas from theoretical models for stellar evolution, including giants as well as main-sequence stars, (2) an initial mass function and birth rate function, (3) a density distribution of stars as a function of distance from the Galactic plane, and (4) a distribution of mass ratios and orbital separations. One reasonably firm conclusion is that masses, even in wide binaries, are correlated: there are too many doubly bright visual binaries (DBVBs), by a factor of 3-5, to agree with the hypothesis that the component masses are selected independently from the same IMF or luminosity function. Another conclusion is that the number of DBVBs per decibel of separation a (absolute, not apparent) is not constant in the range a = 10-100,000 AU, but instead decreases slowly with increasing a. 21 refs.