1 / 25

Binarity & Symbiotics

Binarity & Symbiotics. Hugo E. Schwarz. Cerro Tololo Inter-American Observatory, NAOA/AURA. Asymmetries in PNe. Most field stars are unpolarized. 3/4 of AGB stars is polarized. (Johnson, Jones 1991, AJ 101, 1735) Most PNe are not circular, many are extreme. Some ~50% have binaries.

rufin
Télécharger la présentation

Binarity & Symbiotics

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Binarity & Symbiotics Hugo E. Schwarz. Cerro Tololo Inter-American Observatory, NAOA/AURA.

  2. Asymmetries in PNe. • Most field stars are unpolarized. • 3/4 of AGB stars is polarized. (Johnson, Jones 1991, AJ 101, 1735) • Most PNe are not circular, many are extreme. • Some ~50% have binaries. • Extreme global asymmetries due to binaries. • Point symmetry due to precession. • Links to symbiotics & symbiotic nebulae. • Different properties of bipolar PNe. Asymmetric PNe 28 Jul - 1 Aug 2003

  3. Bipolar properties • Scale height 130pc v. 260pc • Nearer pure circular Galactic rotation • Hotter central stars 145kK v. 75kK • He, N, & Ne are overabundant • Vexp higher 150km/s v.15km/s • Large size 0.76pc v. 0.1pc • More massive progenitors >1.5M Asymmetric PNe 28 Jul - 1 Aug 2003

  4. Bipolars-Symbiotics-PNe • 40% of D&D’ symbiotics have nebulae. • Post-PN nebulae: BI Crucis (3 nebulae). • AS201 fossil PN, ionized nebula, G star. • 5/14 symbiotic nebulae are bipolar. • Binaries explain both phenomena. • M2-9 needs faint, hot star  binary. • Blue-red shifts in the same lobe (IC4234). • Point symmetry explained by precession. Asymmetric PNe 28 Jul - 1 Aug 2003

  5. Symbiotics with optical nebulae Name Type Size[“] Shape Vexp [km s-1] AG Peg(?) S 8 irregular AS 201 yellow 13 elliptical 16 BI Cru D 150 bipolar+jet up to 280 CH Cyg S 32 jet+irregular >65 (>>?) H 1-36 D 0.9-1.5 H 2-2 (?) S 1.4 HBV 475 S 0.4 irregular He 2-104 D 95 2 bipolar+jet 6 to 240 He 2-147 D 5 ring 100 HM Sge D 30 irregular >65 R Aqr D 120 bipolar+jet 55 to 500 RX Pup D 4 bipolar? >80 V417 Cen yellow 100 bipolar 10: V1016 Cyg D 20 elliptical >30 Corradi et al. 1999 A&A 343, 841 Asymmetric PNe 28 Jul - 1 Aug 2003

  6. Symbiotic nebulae Asymmetric PNe 28 Jul - 1 Aug 2003

  7. Symbiotic nebulae (SyNe) • Nearly 4 times more are bipolar cf. PNe. • Average Vexp is 140km/s as for BPNe. • Average z = 133pc as for BPNe. • For BSyNe z = 98pc (only 5 objects) • Most have [NII] as strongest lines. • SO SYMBIOTIC NEBULAE SHARE MANY PROPERTIES WITH BPNe & are binaries… Asymmetric PNe 28 Jul - 1 Aug 2003

  8. BI Cru Post-PN-Nebula Schwarz & Corradi 1992, AA 265, 37 Model of Morris 1987, PASP, 95, 1115 BINARY Vexp = 280 km/s VH = 3000 km/s Central reversal 2 nebulae: H/L exc. D = 1.8kpc S = 1.3pc, Age = 3ka L = 4300L High excitation nebula (unresolved) Asymmetric PNe 28 Jul - 1 Aug 2003

  9. M2-9: PN & symbiotic BINARY! Size = 115“, outer lobes point symmetric, Inner nebula has plane symmetry. Outer lobes reflecting dust L=553L; d=640pc; age=1200yrs; s=0.37pc Both plane and point symmetries due to binary orbit phenomena: rotating central dustclouds and precession? “Symbiotic“ emission lines, prob. disk. [OIII] line, so hot, subluminous *: WD+MS or RG are present = binary. HST image Schwarz et al. 1997 AA 319, 267 Doyle et al. 2000 AJ 119, 1339 Asymmetric PNe 28 Jul - 1 Aug 2003

  10. Vexp=308km/s S = 0.37 pc 34” L = 340 L D = 2.1kpc Age = 624 a Sa2-237 BINARY! As M2-9: [OIII] present, low L, so WD, so binary. Study CS…. Asymmetric PNe 28 Jul - 1 Aug 2003

  11. Schwarz 1991 A&A 243, 469 AS 201 AS201: P-PN-N in the making? Low excitation nebula, old, faint, extended. High excitation inner nebula. Symbiotic & PN. When CS forms disk… get an object like BI Cru? Asymmetric PNe 28 Jul - 1 Aug 2003

  12. A79, He2-428, M1-91Rodriguez, Corradi, Mampaso 2001 AA 377, 1042 Strong mass loss/exchange in unresolved cores. CaII triplet in emission, high , excretion disk. Cont. and absorption lines indicate hot star with cool companion. Equatorial rings and polar lobes. Asymmetric PNe 28 Jul - 1 Aug 2003

  13. Precession, point symmetry Red and blue shifts on the same side of the object. Only if LoS or Sky cut precession cone. IC4634 Long slit spectrum. VELOCITY Observed in IC4634 SPATIAL Asymmetric PNe 28 Jul - 1 Aug 2003

  14. Asymmetric PNe 28 Jul - 1 Aug 2003

  15. Strong links: PNe-Symbiotics-Binaries • All (extreme) bipolars are binaries • All symbiotics are binaries • Evolutionary stage is important (P-PN-N) • Some equatorial density enhancement • Orientation effects should occur • Model these, cf. observations. Asymmetric PNe 28 Jul - 1 Aug 2003

  16. Inclination effects. High inclination objects hide the central object behind their equatorial mass concentration, and therefore show more FIR radiation; low inclination objects show the central object and this increases the fraction of visible & NIR light we see. So… Computing the UBV (VIS),JHK (NIR), & IRAS (FIR) relative fraction of the total flux, we should see an effect. Asymmetric PNe 28 Jul - 1 Aug 2003

  17. Crude model of inclined nebulae • Donut (BB) around point source (BB) • Stellar flux captured is converted toIR • Random i orientation in space • Plot fractions of BVR, JHK, & IRAS (i) • Cf. observations for various BBs: • Donut 600K; Star 10, 20, 40, 80kK Asymmetric PNe 28 Jul - 1 Aug 2003

  18. Observed sample • ~30 objects, partial SEDs, some distances • Estimate inclinations from images (3x) • Use BVR, JHK, IRAS “bands” relative to sum of these bands. • Do same for simulation data, compare. Asymmetric PNe 28 Jul - 1 Aug 2003

  19. Observed sample FIR VIS & NIR Asymmetric PNe 28 Jul - 1 Aug 2003

  20. Random sample • Generate random binaries. • i random with sin(i) histogram • Donut dust distribution, 15% stellar • Plot same parameters as observed data. Asymmetric PNe 28 Jul - 1 Aug 2003

  21. Random sample 1000WD 200RG 200K dust 1000WD 200RG 400K dust  = FIR  = NIR  = VIS Asymmetric PNe 28 Jul - 1 Aug 2003

  22. High inclination (>45) Sa2-237 I=70 2.1kpc 340 Lo M2-9 I=75 0.64kpc 553 Lo He2-104 I=50 1kpc 205 Lo He2-111 I=70 2.8kpc 440 Lo M1-16 I=70 1.8kpc 194 Lo 346 Lo Low inclination (<45) R Aqr I=20 0.2kpc 2800 Lo BI Cru I=40 1.8kpc 4300 Lo 3550 Lo There is some indication of lower luminosities being associated with high inclinations. LUMINOSITIES Another predicted effect is that high inclination objects should have lower apparent luminosities due to the fact that only the equatorial “donut” is seen, while for low inclination the central object plus donut is observed giving an apparent over-luminosity. Over all angles, averaging makes sure that no energy conservation laws are broken; Ltot = n.Lave Distances being uncertain for all but a few objects, we have: Asymmetric PNe 28 Jul - 1 Aug 2003

  23. Luminosity v. inclinationfrom the same simulation. Asymmetric PNe 28 Jul - 1 Aug 2003

  24. Note that the number of objects increases with inclination as sin(i); this is expected just from the statistics of randomly orientated objects, and is strengthened by observational selection of bipolars by their morphology. Objects that are (near) pole-on are not recognized as bipolars and are therefore selected against. We have: 0 - 303 objects 31- 6011 objects 61- 9014 objects This is the expected behavior and is of the right order but there are too few objects to make this harder. Statistics Asymmetric PNe 28 Jul - 1 Aug 2003

  25. Conclusions • PNe, SyNe are linked. • PNe, SyNe are often indistinguishable • Asymmetrical nebulae ( nearly always) have binaries. • Orientation effects are important in interpreting & constraining observations. Asymmetric PNe 28 Jul - 1 Aug 2003

More Related