Scattering phase function
= Scattering phase function
{title2=$P(\Theta)$}
A <scattering phase function> describes the angular distribution of single-scattered power. One common convention is $\int P\,d\Omega=4\pi$, so that $P/(4\pi)$ is a probability density over outgoing <solid angle>. For unpolarized <Rayleigh scattering>, $P=3(1+\cos^2\Theta)/4$. It is distinct from the oscillatory-integral meaning of phase function.