Eric Lagadec for Olivier Chesneau

Transcription

1 Observations of binaries (with focus on PNe and PPNe) Eric Lagadec for Olivier Chesneau (Observatoire de la Cote d Azur) Why galaxies care about AGB stars III

2 Morphologies of AGB and post-agb envelopes 80 % of PNe are non-spherical! (Balick 2002) Almost no PPNe are spherical! (Sahai 1998, Lagadec 2011) 20 AGB star Different PNe

3 Need for equatorial overdensities For theoritical works, see talks by S. Mohamed,R. Izzard, P.J. Davis Poster by S. Toupin Chemical composition, see talks by D. Kamath, L. Guzman, S. Van Eck, C. Galan, Posters by T. Masseron, D. Karinkuzhi, A. Klavins PNe shaping models (Balick & Frank 2002)

4 Direct detection of binaries High angular resolution techniques (AO, interferometry, lucky imaging ) Olivier was hoping to directly image binaries with AO or interferometry Problems: AO: limited angular resolution Interferometry: limited sensitivity and baselines

5 Interferometry with the VLTI Van-Cittert-Zernicke theorem: «The complex visibility is the Fourier transform of the source intensity distribution on the sky at the spatial frequencies corresponding to the projected baseline on the sky per observing wavelength.»

6 Detection of discs with MIDI HST observations A disc!!!!! MIDI visibilities for different baselines orientations Chesneau et al. (2006, 2007, 2008), Matsuura et al. (2006), Lagadec et al. (2006, 2007), Lykou et al. (2011)

7 Torii NGC 6302 Hen Gas/kinematic Dust/no kinematic Peretto et al., 2007 (JCMT/mm) Lagadec et al., 2006 (VLT/IR) Massive (1 solar mass for NGC 6302) Slow expansion, limited angular momentum If gas supply ceases: structure slowly vanishes

8 Stratified disks Isella et al., 2006 (YSO) Clear vertical stratification Small aperture angle (<10 degrees) Keplerian rotation (longer lifetime)

9 Examples of stratified disks Red Rectangle Keplerian Menzel 3 Bujarrabal et al., 2013 RV Taus Deroo et al., 2007 See talk by M. Hillen Chesneau et al., 2007

10 A double disk in M2-9: binaries? M2-9 IRAM HST Two rings (short mass loss episodes) Dynamical imprint: presence of a binary system (P=90 yr) Lykou, Chesneau et al Castro-Carrizo, Neri, Bujarrabal, Chesneau et al. 2012

11 Corradi 2007 Multipolar jets: precession? Jet precession (sahai & traugger 1998) Sahai & Trauger (1998): A disc is not enough, need precessing jets

12 Outflow/jets momentum CRL 618 He CRL 2688 Bujarrabal et al. 2001: 28/32 Post-AGB stars (PPNe) showing CO emission, have outflow momenta in excess to what radiation can provide. See poster by B.M. Lewis

13 Formation of a bipolar/multipolar PN Long debate binary vs magnetic field Binaries Binaries Debate settled during a football game in La Palma (APN4, 2007)

14 Formation of a bipolar/multipolar PN Long debate binary vs magnetic field Soker (2005): a single star can not supply enough energy and angular momentum to shape those nebulae Nordhaus et al. (2006): magnetic fields can play an important role but isolated stars can not sustain a magnetic field for long enough See talk by W. Vlemmings for magnetic field and poster by L. Sabin

15 Different types of binary interactions See talks by S Mohamed, R.Izzard, A. Jorissen, S. van Eck Figure from Pols, 2005

16 Direct detection of binaries in PNe APN4, La Palma (2007): PlanB, community effort to look for binaries in PNe Methods: Flux variability (eclipses, tidal deformations, irradiation effects) Spectral variability (radial velocities) IR excess from a cool companion

17 Binaries in PNe See poster by A. Jorissen A great community effort (B Miszalski, D. Jones, H. Bond, D. Frew, O. de Marco, D. Douchin, S. van Eck, H. van Winckel, A. Jorissen etc..) demonstrates that binaries are common in PNe!

18 Fleming 1 Prototype point-symmetric: closing the case Boffin et al. 2012, Science

19 A close binary Fleming 1 Boffin, Miszalski et al. 2012, Science 15-20% of CSPNe are close binaries (P< 3 days): common envelope? (Miszalski et al., 2009)

20 Jets/common envelope Fleming 1 See Poster by B.M. Lewis Precessing jets, timescale~10 4 yrs Would expect P orb yrs! But close binary! CE after the jets formed. Wind mass transfer before!

21 Binaries in post-agb Problem: stars are pulsating and embedded in dust O H Red Rectangle Masers position: 2 stars Gomez et al., 2001 Waelkens et al., 1996 Radial velocities: binary, p=318 days But the main star is an AGB star

22 Long term monitoring in PPNe B. Hrivnak and undergrads: observations since 1994!!! Hrivnak et al., 2011 Wide binaries hard to detect: we would not know if most PPNe are wide binaries Possibly one binary detected: P>22 years Next: edge-on disks (inclination known) Problem: dust ; solution: IR studies

23 RV Tau stars, a.k.a van Winckel s stars Binary separation AU: close binaries Dusty keplerian disks r 10 au Near infrared excess No visible nebulae Talk by M. Hillen Poster by I. Gezer Radial velocities: 6/6 are binaries (van Winckel et al. 2009)

24 My personal opinion is that the discovery of a stratified disk with proved Keplerian kinematics is directly connected to the influence of a companion, albeit the few exceptions presented above, namely the Young Stellar Objects or the critical velocity rotating massive sources such as Be stars. This hypothesis must be confirmed by further observations. Olivier Chesneau

25 Kervella et al., 2014 Hofmann et al., 2001 Kim et al., 2013 Asymetries already on the AGB! IRC Leao et al Weigelt et al Poster D. Keller V Hya Hirano et al., 2004 Sahai et al., 2003 L 2 Pup CIT 6 Schmidt et al alks Ohnaka, Lykou, Montarges

26 Influence of a binary: R Scl See talks by M. Maercker, W. Vlemmings Maercker et al., 2012

27 Spiral patterns and binarity 3D SPH models Mass-losing AGB star + companion (wide binary, 50 AU) Spiral shock covering most of the solid angle Mastrodemos & Morris (1999)

28 Wind Roche-lobe overflow AGB star mass: 1.6 M Companion: 0.25 M Separation: 60 AU Mohamed and Podsiadlowski, (2007) See talk by S. Mohamed

29 Wind Roche lobe overflow Observations Model Maercker et al., 2007 Spiral: indirect evidence for binary companion!

30 More spirals: binaries! CIT 6 AFGL 3068 Kim et al., 2013 Mauron & Huggins (2006), HST Hunt for binaries: large imaging survey? (optical,mm,ir (coronographic))

31 Observing large scale interactions Mira: influenced by companion and ISM! Wind of AGB star interacts with companion : largescale asymmetries in the AGB wind Observed by dust (Herschel) and molecular emission (ALMA) [galex] [Herschel] [Chandra]

32 Small and large scale interaction See talks by C. Paladini, F. Lykou, M. Wittkowski, G. Perrin, X Haubois, Poster by J.Hron, P. Cruzalebes, L.D. Matthews, P.T. Nhung, D.T. Hoai Mapping envelopes from dust formation till interaction with the ISM Mass-loss history (departure from spherical symmetry)

33 Detections methods for binaries in AGBs Pulsations + dust : not possible to use RV, photometric variability or IR excess! Look for UV excess (accretion in binary systems) (Sahai et al. 2008, 2011) Galex UV flux UV Excess UV excess in the AGB star Y Gem (Sahai et al. 2008)

34 Binaries in the LMC/SMC Distance known: P-L relation, orbits 7-9% Of PNe precursors Binaries Woods et al., 1999 Many objects are post-rgb!!!!!: due to binaries? Nicholls et al., 2010 See talk by D. Kamath, Poster by P.Wood

35 Binaries with interferometry? SV Psc HD 352 Mysterious star Boffin et al., 2014 Optical/IR interferometry with 4 telescope ALMA with 66 antennae Olivier s dream soon to be fulfilled?

36 Effects of binarity on evolution Creation of a disk (dust processing, dual dust chemistry) Quick envelope ejection (less dredge-up, most O-rich PNe are aspherical, no AGB phase?) Enrichment of secondary in s-elements (peculiar stars like Barium stars, CEMP, CH stars..) No PNe without binaries? (De Marco, but not what is observed in the LMC/SMC) In the case of RV Tau stars, no PNe

37 Conclusions and perspectives Binaries are common in PNe Should also be in AGBs! (or in RGBs?) Would impact morphologies but also dust/chemical composition (e.g. envelope ejected before dredgeup, peculiar chemical composition) Need to study disks formation and evolution and impact on the star (depletion on dust, mass-loss history ) Shall we hunt for binaries like the PN community did? (and compare RGB/AGB/PPNe/PNe binary fractions)

38 Merci Olivier! Please send us answers to these questions!