1. E. Khomenko and M. Collados
EFFECTS OF PARTIAL IONIZATION IN THE PHOTOSPHERE AND IN THE CHROMOSPHERE
E. Khomenko and M. Collados

2. Approximation of magnetohydrodynamics+
Fully ionized
Coupled by collisions
Single fluid description

4. photosphere
chromosphere

5. Approximation of magnetohydrodynamics Multi-fluid approximation+ B +
Fully ionized
Coupled by collisions
Single fluid description
Weakly ionized
Less coupled by collisions
Sunspots and chromosphere
Best valid in the deep photosphere and convection zone

6. Equations of Magnetohydrodynamics

7. Equation for individual species

8. Combined quasi-MHD equations

9. Diffusivities

10. Conversion of magnetic to thermal energy

14. Z = 1000 km
900 G
750 G
600 G
450 G
300 G

15. Z = 1000 km

18. Conclusions
Collissions with neutrals (ambipolar diffusion)
can lead to a significant temperature rise
(~ 2000 k) within minutes at chromospheric
level
Important plasma motions can appear during
the heating process