S wave (quantum scattering)
= S wave
{disambiguate=quantum scattering}
{c}
{title2=$l=0$}
= S-wave scattering
{c}
{synonym}
An S wave is the rotationally invariant angular-momentum channel $l=0$. At sufficiently low energy it normally dominates short-range scattering because higher partial waves are suppressed by their centrifugal barriers.