There are gravitational effects that draw the photons emmited from the outer edges toward the centre of the sun-observer axis in accordance with einsteins theory of general relativity. So the photon energy is decreased as energy is lost gravitationally, therefore further redshifting emmitted...
have solved the lane - emden eqn numerically for scaled radius, and the derivative of scaled pressure with respect of scaled radius, are given the eqn of state, n, and mass, how would i go about working out the central density and the radius?
thanks