Radiative Transfer in Spherically Symmetric Dust Nebulae

In this paper the mathematical tools for future calculations of the diffuse radiation field inside a homogeneous spherically symmetric dust nebula are made available. The solution of the equation of radiative transfer is represented as an expansion after LEGENDRE polynomials. Making use of the operator calculus a system of ordinary differential equations is derived the solution of which yields the coefficients of this expansion. The method developped here is more general as well as more rigorous than previous work in this field.