Stellar electron-scattering Eddington factor (${\Gamma }_e={\kappa }_{e}L/(4\pi cGM)$)

This factor is the ratio of acceleration due to electron-scattering opacity to gravitational acceleration in a spherical luminous star. The remaining effective gravity is approximately $GM(1-{\Gamma }_e)/R^2$ when other radiative forces are neglected. Being below the electron-scattering limit does not preclude a line-driven stellar wind, because additional opacity can provide more acceleration.