1 / 14

The VLTI view of compact dusty environments around evolved stars

Olivier CHESNEAU Observatoire de la Côte d’Azur (OCA) F. Lykou, E. Lagadec, A. Zijlstra (Univ. Manchester), S. Sacuto, P. De Laverny (OCA), O. De Marco (MNH), M. Matsuura (UCL), G. Clayton (Univ. Baton Rouge), B. Balick (Univ. Washington), N. Smith (Berkeley).

rupert
Download Presentation

The VLTI view of compact dusty environments around evolved stars

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. Olivier CHESNEAU Observatoire de la Côte d’Azur (OCA) F. Lykou, E. Lagadec, A. Zijlstra (Univ. Manchester), S. Sacuto, P. De Laverny (OCA), O. De Marco (MNH), M. Matsuura (UCL), G. Clayton (Univ. Baton Rouge), B. Balick (Univ. Washington), N. Smith (Berkeley) The VLTI view of compact dusty environments around evolved stars To be or not to be a disc?

  2. VLTI at ESO Paranal, Chile The MIDI interferometric observations of compact dusty environnements

  3. VLTI Instruments MIDI: Mid-Infrared (8-13 mm) 2-way beam combiner. Spectral resolution R=30 (prism), R=230 (grism). Spatial resolution: 5-20 mas One visibility spectrum per observation, photometric spectrum, differential phase (see Deroo et al. 2007) AMBER: Near-Infrared (J, H, K; 1-2.5 mm) 3-way beam combiner. Spectal resolution: R=30 (low resolution), 1500 (medium r.), 12000 (high r.). Spatial resolution: 2-5 mas Results: 3 visibility spectra, 3 differential phases and 1 closure phase spectrum per obs, continuum corrected spectrum of the source. The MIDI interferometric observations of compact dusty environnements

  4. CPD –56 seen at different spatial scales 10 mm simulation 0.1 arcsec MIDI 8.7 mm image 1 arcsec 12 arcsec HST Chesneau, O., Collioud, A., De Marco O. et al., 2006, A&A The MIDI interferometric observations of compact dusty environnements

  5. VISIR 12.8mm [NeII] An amorphous silicate disc in the Ant nebula, Mz 3 HST observations MIDI visibilities for different baselines orientations The MIDI interferometric observations of compact dusty environnements

  6. 140 mas - 100 AU Density (2d disk)with α = 2.4 β = 1.03 h100AU = 17 AU β = 1.03 h(100 UA)=17 UA α = 2.4 Rin = 9 AU 200AU 500 AU The MIDI interferometric observations of compact dusty environnements

  7. See poster Foteini Lykou et al., #34 The MIDI interferometric observations of compact dusty environnements

  8. A silicate disc in the Butterfly nebula M2-9? B=40 m PA=107 ° To be continued… The MIDI interferometric observations of compact dusty environnements

  9. New observations (PI: E. Lagadec) with 4 new baselines just obtained OH 231.8+3.4: not a disk but a highly distorted dusty shell MIDI observations of the post-AGB star OH 231.8 (Matsuura, Chesneau et al. (2006)) The MIDI interferometric observations of compact dusty environnements

  10. Formation of OH 231.8 +3.4 Soker & Livio (2001) In the context of…M 2-9 The MIDI interferometric observations of compact dusty environnements

  11. WD MIRA The symbiotic system HM Sge: an ‘almost’ normal Mira • HM Sge : • Dusty symbiotic system (d~1.5 kpc), large separation 40mas~60 AU (Sources isolated with HST, Eyres et al. 2001) • Nova-like explosion (1975), unknown system before • Cold component: Mira (3000 K) + Hot component: White Dwarf (2105 K) The MIDI interferometric observations of compact dusty environnements

  12. HWHM~8 mas at 8.5mm (~12AU), flattening 0.8, Major axis perpandicular to binary orientation HWHM~13 mas at 13.5mm (~22AU), flattening ~1 3.5mas Teff=3000K Tin=1600K 10 = 2.5 N E U3-U4(~100°) E0-G0(~75°) U2-U3(~45°) MIDI Observations with UTs/ATs: 6 bases Various DUSTY models from literature tested, Double shell models discarded (Schild et al. 2000, Bogdanov & Taranova 2001) Sacuto, S., Chesneau, O., Vannier, M., et Crusalèbes, P. 2007, A&A, 465, 469 The MIDI interferometric observations of compact dusty environnements

  13. p1 Gruis : • Nearby J star (153 pc) • A visual companion at large distance (G0V, 2.7’’- 400 AU) • A ‘disc’ (equatorial overdensity) and a fast (50km/s) outflow seen in millimetric observations (CO, Chiu et al. 2006) • Data indicate a spherical dusty wind + molecular atmosphere Sacuto, S., Crusalèbes, P., Jorissen, A., Chesneau, O., Ohnaka, K 2007, A&A, submitted The MIDI interferometric observations of compact dusty environnements

  14. Summary • CPD-568302: Inner disc resolved with MIDI (Chesneau et al. 2006) but large uv coverage needed to precise the geometry • OH231.8: the ‘polar’ size of dust emission measured (after Matsuura et al. 2006). There is a distorted, mildly flattened dusty structure, large uv coverage probably needed, complex geometry • Mz-3: a 10-30mas (15-45 AU) disc is resolved with MIDI, a good disc model reached with amorphous silicate dust (see poster of F. Lykou, #34), • M2-9: MIDI observations under way, major axis > 45mas - 70 AU (larger than Mz3, crystalline silicates) • HM Sge: the Mira wind only slighly affected by the WD (Sacuto et al. 2007a), • p1 Gruis: A close J carbon star forming an extended equatorial overdensity (Sacuto et al. 2007b) • Many other applications of MIDI/VLTI for evolved stars: • Discs around post-AGB binaries (P. Deroo to come) • Monitoring of novae outburst (RS Oph, V1280 Sco) • Monitoring of the dusty clumpy environment of R CrBs (Leao et al. 2007), • Studying the MOLsphere of evolved stars (Ohnaka et al. 2003, 2006, 2007) The MIDI interferometric observations of compact dusty environnements

More Related