I have solved the problems of rayleigh scattering and thanks to help of members here, created a new ring with buggy tools. Now I am curious about one more thing.
Is it possible to simulate forward scattering? Planet rings are brighter when viewed from the opposite side of the light source. I tried using the SSS shader but it does not replicate the effect. I would try using a volume shader (since anisotropy controls back versus forward scattering) but 2D textures do not influence volume density (I am using a radio occultation map of saturn's rings as the alpha texture).