Magellanic Cloud planetary nebulae as probes of stellar evolution and populations. Letizia Stanghellini

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

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 Planetary nebulae beyond the Milky Way - May 19-21,

probes of post-agb evolution Benchmarks for extragalactic PN

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

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

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? Planetary nebulae beyond the Milky Way - May 19-21,

From Galactic PNe: Round, Elliptical, Bipolar [includes bipolar core and multipolar], and Point-symmetric

6 Symmetric Asymmetric 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 6

bipolar (or multi-polar) (B) 9% have an equatorial enhancement,

7 HST and spatial resolution LMC SMP 10 HST STIS arcsec arcsec

8 8 Slitless Spectra of LMC SMP 16 G430M ( ) and G750M ( ) _5007 [O III] _4959 [O III] _4861 Hβ 6732 [S II] 6716 [S II] 6584 [N II] 6563 Hα 6548 [N II] _6300 [O I]

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

10 Morphological distribution Round R Elliptical E R+E (symm.) Bipolar B Bipolar core BC B+BC (asymm.) LMC 29 % 17 % 46 % 34 % 17 % 51 % SMC 35 % 29 % 64 % 6 % 24 % 30 % Point-symmetric 3 % 6 % 10

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 nonmagnetic WDs! Wickramasinge & Ferrario 2000) Binary evolution of the progenitor (CE)? Morris 81; Soker 98 11

Garcia-Segura 97 (single magnetic WD are more massive than nonmagnetic

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 Planetary nebulae beyond the Milky Way - May 19-21,

Ne are invariant during the evolution of stars in this mass range they are signature of the

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

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

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

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

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

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

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

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

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

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 er (residual envelope mass at EEQ) determines t tr τ dyn =D PN /v exp represent the dynamic PN age. If D PN is measured on main shell, τ dyn tracks time from EEQ τ dyn =t tr + t (t ev ev = time after PN illumination, corresponding to evolutionary time if tracks have zero point at illumination) 22

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 er now known Only way to constraint t tr is observationally > Magellanic PNe offer the first direct estimates of transition time Planetary nebulae beyond the Milky Way - May 19-21,

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

25 Distribution of t tr in MC PNe 25

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

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) 27

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

29 MA 1796 MA 1797 MG 2 Log Fβ C Size [arcsec] Size [pc] Planetary nebulae beyond the Milky Way - May 19-21,

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

31 Cloudy models Galaxy LMC SMC Nuclear reactions end PN + CS trans. Super-wind TP-AGB AGB Cooling WD T eff L 31

32 Cloudy models, varying density SMC LMC Galaxy 32

33 PN cooling in different galaxies Our HST data: LMC <I(5007)/I(Hβ)>=9.4 (3.1) <I(1909)/I(Hβ)>=5 (5) SMC <I(5007)/I(Hβ)>=5.7 (2.5) UV: Cycle 13 SMC LMC Galaxy 33

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

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

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 Planetary nebulae beyond the Milky Way - May 19-21,

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]/Hβ flux ratio of a PN population variant with host galaxy Planetary nebulae beyond the Milky Way - May 19-21,

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

Faber-Jackson relation: Fundamental Plane: Faber-Jackson Relation

Faber-Jackson relation: Fundamental Plane: Faber-Jackson Relation Faber-Jackson relation: Faber-Jackson Relation In 1976, Faber & Jackson found that: Roughly, L! " 4 More luminous galaxies have deeper potentials Can show that this follows from the Virial Theorem Why