= Flattening–anisotropy virial relation
{title2=$\Pi_\perp/(2\Pi_{zz})=1+\gamma(q^{-2}-1)/5+O((q^{-2}-1)^2)$}
For a pressure-supported scale-free tracer $\rho\propto(R^2+z^2/q^2)^{-\gamma/2}$ in a spherical <Newtonian gravitational potential>, the <tensor virial theorem> constrains integrated directional <velocity dispersions>. Modest oblate flattening and a decreasing radial <mass density> require greater in-plane random support per direction. The displayed expansion assumes finite global virial integrals; the corresponding ratio of force moments also has a cutoff-independent angular interpretation.
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