| 81 | Now, depending on position, the internal energy will either decrease or increase. Recall, |
| 82 | |
| 83 | [[latex($\frac{\partial(\rho e)}{\partial t} = -\kappa_R (4 \pi B - cE)$)]] |
| 84 | |
| 85 | So in close in to the source, E>B, but further away (where diffusion was weaker), B>E. Thus, after a hydro timestep we have: |
| 86 | |
| 87 | [[Image(thydro.png, 35%)]] |
| 88 | |
| 89 | This means, depending on the relative strengths of coupling and diffusion, there will be some regions of radiative heating and some of cooling. For this picture here (which is very rough -- a diffusion wave, and coupling 'wave' may have different concavity than shown here): |
| 90 | |
| 91 | [[Image(heatingregions.png, 35%)]] |
| 92 | |