7 SHORTrad

Operator

• gives $\Delta\rho e_{\rm i}/\Delta t$,

• works for small and large optical depths,

• cools only hot cells.

Interpolation

• averages only incoming intensities,

• not $S$ nor $\kappa$ nor Flux.

Scheme

• can handle extrem jumps in opacity, temperature, and/or heat capacity.