On the distribution of orbital eccentricities for wide visual binary stars

We propose to determine the form of the eccentricity distribution for wide visual binaries from the distribution of the angle between the radius vector that connects the components and the vector of their relative motion. The available data indicate that the distribution of angles for physical binaries with periods similar to 10(3)-10(4) years is uniform. We show that it corresponds to a linear distribution of eccentricities, f(e) = 2e, which is typical of systems that are formed by the breakup of small clusters or unstable multiple stars.