1. Planetary nebulae beyond the Milky Way - May 19- 21, 2004 1 Magellanic Cloud planetary nebulae as probes of stellar evolution and populations Letizia Stanghellini

2. Planetary nebulae beyond the Milky Way - May 19-21, 2004 2 Magellanic Cloud PNe The known distances, low field reddening, relative proximity, and metallicity range make them  Absolute probes of post-AGB evolution  Benchmarks for extragalactic PN populations

3. Planetary nebulae beyond the Milky Way - May 19-21, 2004 3 Probes of post-AGB evolution Nebular analysis Morphology chemistry Links to central stars (CSs) Transition time Winds

4. Planetary nebulae beyond the Milky Way - May 19-21, 2004 4 Benchmarks for extragalactic PN populations PNe and UCHII regions Luminosity distribution and metallicity PNe types in the PNLF

5. Planetary nebulae beyond the Milky Way - May 19-21, 2004 5 PN morphology ·Depends on the formation and dynamic evolution of the PN, on the evolution of the central star and of the stellar progenitor, and on the environment. ·From Galactic PNe: ·Round, Elliptical, Bipolar [includes bipolar core and multipolar], and Point-symmetric ·Bipolar PNe are located in the Galactic plane, have high N, He, indication of massive CSs: remnant of 3-8 M stars?

6. 6 Round PNe (R) are a minority (22 % of all Galactic PNe with studied morphology) 49% elliptical (E) 17% bipolar (or multi-polar) (B) 9% have an equatorial enhancement, or ring (lobe-less bipolar, or bipolar cores) (BC) 3% point-symmetric Symmetric | Asymmetric

7. 7 HST and spatial resolution LMC SMP 10 HST STIS  -----3 arcsec -------   ------------35 arcsec ---------------------- 

8. 8 _4861 H  _4959 [O III]_5007 [O III] _6300 [O I] 6584 [N II]6563 H  6548 [N II] 6732 [S II]6716 [S II] Slitless Spectra of LMC SMP 16 G430M (4818 — 5104) and G750M (6295 — 6867)

9. 9 Round Elliptical Bipolar Point-symmetric Galaxy LMC SMC Symmetric | Asymmetric

10. 10 Morphological distribution LMCSMC Round R29 %35 % Elliptical E17 %29 % R+E (symm.)46 %64 % Bipolar B34 %6 % Bipolar core BC17 %24 % B+BC (asymm.)51 %30 % Point-symmetric3 %6 %

11. 11 What is the physical origin of the equatorial disks? stellar rotation? Maybe associated with a strong magnetic field? Garcia-Segura 97 (single magnetic WD are more massive than non- magnetic WDs! Wickramasinge & Ferrario 2000) Binary evolution of the progenitor (CE)? Morris 81; Soker 98

12. Planetary nebulae beyond the Milky Way - May 19-21, 2004 12 Chemistry ·PNe enrich the ISM ·He, C, N, O abundances are linked to the evolution of the progenitors ·C-rich for massive progenitors (M ZAMS < 3 Msun) ·He- and N-rich (and C-poor) if M ZAMS > 3 Msun ·Ar, S, Ne are invariant during the evolution of stars in this mass range  they are signature of the protostellar ambient, thus test previous evolutionary history

13. 13 Primordial elements, LMC O Round * Elliptical  Bipolar core Bipolar  LMC HII regions (average)

14. 14 Primordial elements, LMC O Round * Elliptical  Bipolar core Bipolar  LMC HII regions (average)

15. 15 LMC PN morphology and the products of stellar evolution O Round * Elliptical  Bipolar core Bipolar  LMC HII regions (average)

16. 16 SMP16 SMP 95 SMP 34 Si IV N IV C IV] He II Decreasing excitation class --->

17. 17 SMP16 SMP 95 SMP 34 C III ] C II] [Ne IV]

18. 18 Optical AND UV morphology C III]1908 C II] 2327 [Ne IV] 2426 nebular continuum LMC SMP 95 Broad band [O III] 5007 [N II] H  [N II]

19. Planetary nebulae beyond the Milky Way - May 19-21, 2004 19 UV spectra fitting

20. Planetary nebulae beyond the Milky Way - May 19-21, 2004 20 P-Cygni profiles

21. 21 Wind momentum vs. luminosity See poster by A. Arrieta

22. 22 Transition time ·Transition time (t tr ) is measured from the envelope ejection quenching (EEQ) and the PN illumination; it is regulated by wind and/or nuclear evolution ·M e R (residual envelope mass at EEQ) determines t tr  dyn =D PN /v exp represent the dynamic PN age. If D PN is measured on main shell,  dyn tracks time from EEQ  dyn =t tr + t ev (t ev = time after PN illumination, corresponding to evolutionary time if tracks have zero point at illumination)

23. Planetary nebulae beyond the Milky Way - May 19-21, 2004 23 Dealing with unsynchronized clocks ·t tr is an essential parameter in post-AGB population synthesis (e.g., PNLF high luminosity cutoff, and UV contribution from post-AGB stars in galaxies) ·Mass-loss at TP-AGB and beyond not completely understood, and M e R now known ·Only way to constraint t tr is observationally · > Magellanic PNe offer the first direct estimates of transition time ·Assumptions: no acceleration of shells; He- tracks scaled to H-burning tracks

24. 24  dyn and t ev LMC SMC Round: symm. PNe (R,E) Square: asymm. PNe (B,BC,P) H-burning central stars

25. 25 Distribution of t tr in MC PNe

26. 26 M e R =1e-3 M e R =2e-3 M e R =5e-3M e R =1e-2 Data LMC PNe SMC Pne Models t wind t nucl t tr

27. 27 Total mass loss (IMFMR) Data: optically thin LMC and SMC PNe Hydro models: solid line =PN shells broken line=outer halos --> To constrain IMFMR we need to measure mass in PN halos (and in CSs)

28. Planetary nebulae beyond the Milky Way - May 19-21, 2004 28 Importance of spatially- resolved PN populations ·We sampled ~50 (+30) LMC and ~30 SMC PNe, chosen among the brightest known (based on on H  and [O III] 5007 fluxes ) ·All LMC PN candidates are indeed PNe ·~10% of the SMC PN candidates are H II regions

29. Planetary nebulae beyond the Milky Way - May 19-21, 2004 29 MA 1796MA 1797MG 2 Log F  C 1.53... 1.4 Size [arcsec] 311 3.5 Size [pc] 0.85 3.1 0.98

30. 30 Observed distributions of I(5007)/I(Hb) LMC SMC

31. 31 Cloudy models Galaxy LMC SMC

32. 32 Cloudy models, varying density SMC LMC Galaxy

33. 33 SMC Galaxy LMC PN cooling in different galaxies Our HST data: LMC =9.4 (3.1) =5 (5) SMC =5.7 (2.5) UV: Cycle 13

34. 34 PNe in the PNLF Open circles: R Asterisks: E Triangles: BC Squares: B Filled circles: P O round; * elliptical;  bipolar core; bipolar LMC SMC Faint----------> bright

35. 35 CSs in PNLF LMC SMC Faint-----------> bright SMC HLCO LMC HLCO

36. Planetary nebulae beyond the Milky Way - May 19-21, 2004 36 Summary, and the future HST fundamental for shapes/ radii, but also for identification (misclassified H II regions in SMC but not in LMC  metallicity effect?) Same morphology types in Galaxy, LMC, SMC, but more asymmetric PNe in LMC than SMC  different stellar generations? Asymmetric LMC PNe have high Ne, S, Ar--> signature of younger progenitors Similar UV and optical morphology

37. Planetary nebulae beyond the Milky Way - May 19-21, 2004 37 Summary, cont. Carbon higher for symmetric PNe, STIS UV spectra of LMC PNe to be analyzed; SMC PNe in Cycle 13 P-Cygni profiles as signature of CS winds, distance indicator for galactic PNe Transition time constrained from observation enlarge sample, hydro+stellar modeling IMFM relation constraints [O III]/H  flux ratio of a PN population variant with host galaxy

38. Planetary nebulae beyond the Milky Way - May 19-21, 2004 38 Symmetric PNe populate the high luminosity parts of the PNLF High mass CSs populate the faint end of the LF, sample to be extended Summary, cont. ·