On the velocity structure in clumpy planetary nebulae Caf é de grano o soluble:

1. On the velocity structure in clumpy planetary nebulae Café de grano o soluble: Micro-estructuras en nebulosas planetarias Wolfgang Steffen Alberto López Instituto de Astronomía UNAM, Ensenada MyPN 5

2. Observations: • Velocities of clumps up to > 500 km/s • Linear velocity gradients for clumps and jets at large distances from the CS • High speed tails up to ~ 200 km/s • Theory: • Magnetic “jets” (García-Segura 1999) &Stagnation knots (Steffen, W. 2001) • show linear v-gradients • This paper: • Quasi-spherical clump distribution • from instabilities and clumpy AGB-remnant • overrun by fast post AGB-wind NGC 2440

3. Borkowski et al. 1995 Borkowski et al. 1995 Borkowski et al. 1995 Abell 30 Chu et al. 1997 (X-Ray)

4. Images and velocities of fast head-tail structures Abell 78 Meaburn et al. 1998

5. Images and velocities of very fast symmetric FLIERs MyCn18, O’Connor, Meaburn et al.

6. García-Segura et al. 1999

7. Stagnation knots Steffen, W., et al. 2001

8. Fast stellar wind in 1 / r^2 environment (AGB-wind) conv. shocks Thermal instabilities Dynamical instabilities shock before cooling Steffen & López in prep.

9. Clumps due to dynamical and thermal instabilities Velocity [cm/s] Distance [units 1e15 cm]

10. Fast stellar wind and pre-existing clumps log number density Steffen & López, in prep.

11. density distribution Shock acceleration of clouds wind ambient medium Speed of cloud after shock

12. Continuous wind acceleration of clouds Simplified equation of motion vc= F ( vi, h, r, vco, ro ) Clump velocity vc_inf= G ( vi, h, vco, ro ) Terminal velocitynot equal local wind velocity For large times evolution becomes self-similar. Steffen & López, in prep.

13. Velocity vs. distance evolution for 2 different clump densities Low density High density

14. Velocity vs. distance for different densities of clouds for fixed time self-similar (low density) not self-similar (high density)

15. Velocity vs. distance scatter plot pre-existing clouds colour is log density 1000 km/s Velocity low density 200 km/s high density distance [cells]

16. Velocity vs. distance scatter plot pre-existing clouds colour is log density low density tails (not modeled) Velocity [cm/s] model distance [cells]

17. Velocity vs. Density scatter plot instability clouds pre-existing clouds 1000 km/s Velocity 200 km/s log density [1/ccm]

18. Velocity spikes from tails of dense clumps Velocity [cm/s] Distance [units 1e15 cm]

19. Conclusions: • Velocity stratification with density • Initial shocked clump velocity ~ 1/r • Linear velocity gradient for large r • Multi-valued velocities at small r and high densities • Velocity structure from instability clumps & • pre-existing clumps is very different • More velocity and density diagnostics needed MyPN 3

20. MyPN 5

21. MyPN 5

22. Preexisting clumps and due to thermal instabilities Velocity [cm/s] Distance [units 1e15 cm]