Lamb frequency
= Lamb frequency
{c}
{title2=$S_\ell^2=\ell(\ell+1)c_s^2/r^2$}
The Lamb frequency is the horizontal acoustic angular frequency of a spherical-harmonic component of degree $\ell$. With <adiabatic sound speed> $c_s$, $S_\ell^2=\ell(\ell+1)c_s^2/r^2$. It helps determine inner acoustic turning points and vanishes for radial modes.