Spherical Jeans equation (source code)

= Spherical Jeans equation
{c}

For a steady nonrotating spherical system,
$$
\frac{d(\rho\sigma_r^2)}{dr}
+\frac{2\beta}{r}\rho\sigma_r^2
=-\rho\frac{d\Phi}{dr}.
$$
It relates radial pressure, velocity anisotropy, and the gravitational field.