SP_N Source Iteration Strategy

• SP_N Equations: Red and Green terms are treated explicitly, equations decouple into M x G separate diffusion equations
• DSA Equations: summing over angle and treating Red terms implicitly leads to G separate diffusion equations, which provide an angle-constant update
• LMFG Equation: summing over group and treating Green terms implicitly leads to a single diffusion equation, which provides a spectrum-scaled update
• These equations are solved repeatedly until the Red and Green terms converge