Estimating random close packing density from circle radius distributions.

Circles of a single size can pack together densely in a hexagonal lattice, but adding in size variety disrupts the order of those packings. We conduct simulations which generate dense random packings of circles with specified size distributions and measure the area fraction in each case. While the size distributions can be arbitrary, we find that for a wide range of size distributions the random close-packing area fraction ϕ_{rcp} under this general protocol is determined to high accuracy by the polydispersity and skewness of the size distribution.