Mass-loss from Evolved stars: High Spatial Resolution Studies

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Mass-loss from Evolved starsHigh Spatial
Resolution Studies

• Olivier Chesneau,
• Observatoire de la Côte dAzur
• Collaborators (many)
• Armando Domiciano Bruno Lopez Sebastian Wolf
  Farrok Vakili
• Florentin Millour Luc Dessart Arnaud
  Collioud Tijl Verhoelst
• Romain Petrov Orsola De Marco Mikako
  Matsuura Eric Lagadec
• Daniel Bonneau Albert Zijltra Michael
  Min Christain Hummel ...

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VLTI short technical description

• VLTIMIDI
• 37 optical elements (33 reflections)
• Until 200m baseline (and 350m of optical path!)
• Automatisation Active optics (M1), chopping
  (M2), adaptive optics, moving delay lines,
  Variable curvature mirrors...

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Preset
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• VINCI K band test interferometer,
• No spectral dispersion,
• Strong point measurement accuracy (1 and
  less),
• Main science objective measurement of stellar
  radii
• Objects studied
• Main sequence stars
• Kervella, P., Thévenin, F., Ségransan, D., et
  al. 2003, AA, 404, 1087
• Kervella, P., Thévenin, F., Morel, P., Bordé,
  P., Di Folco, E., 2003, AA, 408, 681
• Kervella, P., Thévenin, F., Morel, P., et al.,
  2004, AA, 413, 251
• Kervella, P., Thévenin, F., Di Folco, E. 2004,
  AA, 426, 297
• Di Folco, E., Thévenin, F., Kervella, P., et al.
  2004, AA, 426, 601
• F. Thévenin, P. Kervella, B. Pichon, P. Morel,
  E. Di Folco, Y. Lebreton, 2005, accepté
• Cépheids
• Kervella, P., Nardetto, N., Bersier, D.,
  Mourard, D., et al., 2004, AA, 416, 941,
• Kervella, P., Bersier, D., Mourard, D., et al.
  2004, AA, 428, 587 ET 2004, AA, 423, 327
• Kervella, P., Fouqué, P., Storm, J., et al.
  2004, ApJ, 604, L113
• Fast rotators

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• MIDI N band interferometer (8-13 micron)
• Spectral dispersion, 30 et 230, accuracy 5-15,
  2 telescopes
• First interferometer of this kind (but see
  Keck),
• Main science goal study of compact dusty
  objects
• Spectral types any with dust
• Young stars disk (all types), evolved stars (all
  types),
• van Boekel, R. Min, M. Leinert, Ch. et al.,
  2004, Nature, 432, 479 Herbig AeBe stars
• Leinert, Ch. van Boekel, R. Waters, L.B.F.M.
  Chesneau, O. et al., 2004, AA, 423, 537
• Chesneau, O. Meilland, A. Rivinius, T. Stee,
  P. et al., 2005, Be star
• Chesneau, O. Verhoelst, T. Lopez, B. et al.,
  2005, accepté, AGB,
• Chesneau, O. Min, M. Herbst, T.et al., 2005,
  accepté, Eta Carinae, supergiant
• Ohnaka, J. Bergeat, T. Driebe et al., 2005,
  AA, 429, 1057 AGB
• Ohnaka, J. Driebe, T. Hofmann, K. et al.,
  2006, AA 445 , 1015 AGB
• Derroo,  P. Van Winckel, H. Min, M. et al.,
  2006 astro.ph 1169 post-AGB
• Abraham, P. Mosoni, L. Henning, Th. et al.
  2006 astro.ph 2334 FU Or object
• AGNs disks,
• Jaffe, W. Meisenheimer, K. Röttgering, H. J.
  A. et al., 2004, Nature, 429, 47, NGC1068

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• AMBER J(1.2?m), H(1.6?m) and K (2.2?m)
  interferometer
• Strong points
• spectral dispersion (1000,10000),
• 3 télescopes recombinaison,
• Multiple science goals potential far from being
  explored
• Objects and phenomena studied
• Main sequence diameters, flattening and
  distortion,
• Young stars disk-photosphere interface,
  cinematic, jets, material exchanges
• Evolved stars mass loss, molecular envelops,
  magnetism
• AGNs accretion disks, jets
• Extrasolar planets study limited to hot Jupiter
  s,
• Several papers accepted or submitted
• Wind-disk interface study of the Herbig AeBe
  MWC297 (Malbet et al., accepted)
• Dusty environment of the Be supergiant CPD-57
  with MIDI et AMBER (Domiciano et al., accepted)
• Study of the truncated disk of the Be star,
  alpha Ara (Meillant, Stee et al., accepted),
• Study of the binary WRO, gamma Velorum,
  (Petrov, Millour, Chesneau, et al., submitted)

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VLTI science contribution

• 2003
• 6 papers (VINCI) versus 17 for the year,
• MIDI commissioning
• 2004
• 15 VLTI papers (12 VINCI, 3 MIDI) versus 27,
• Active concurrence!
• Keck interferometer (2 papers in 2004),
• IOTA, PTI, et NPOI,
• AMBER commissioning,
• 2005 14 VLTI papers (9 VINCI, 5 MIDI),
• First CHARA papers (5),
• Keck interferometer (5),
• 30 papers published
• Information from http//olbin.jpl.nasa.gov/
• (Optical Long Baseline Interferometry News )

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A complementary tool Adaptive Optics NACO
Some typical numbers . L PSF FWHM 100mas,
strehl60-75, Dec 50-60mas . K resolution
60mas, Strehl20-40, . Dynamical range
103-104
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Mass loss from evolved stars loss of spherical
sphericity I- Massive stars (Hot)
Associated issues . Binarity, . Rotation, . X
ray generation in radiative winds, . Supergiant
eruptions and instabilities, . Supernovae Ib,c,
II remanent geometry . Dust production from hot
stars . LBVs, . Be, . WR of carbon type,
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The tip of the iceberg!
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Smith et al., 2002, 2003
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Understanding the visibilities with simple
geometric models
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Star flux and dust clumping
N
E
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The central star
Question what is the influence of the dust
extinction on the inferred parameters of the
model?
Chesneau, O., Min, M., Herbst, T. et al., 2005
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The Be phenomenon(Lamers et al. 1998)
Supergiants Be ? L/Lsun gt 104
Observations point towards asymmetrical stellar
environments
Zickgraf et al. (1985)
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VLTI/MIDI spectrum and visibilities
Domiciano de Souza, Driebe, Chesneau et al. 2006
AA (astro-ph/0510735)
Be supergiant star CPD-57 2874
Gaussian models 2a (10.1?0.7) (2.6?0.4)
(?-8?m) mas Axial ratio 2b/2a 0.76
?0.11 Position angle PA 145 ? 6
2a (15.3?0.7) (0.45?0.22) (?-12?m) mas Axial
ratio 2b/2a 0.80 ?0.10 Position angle PA 143
? 6
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VLTI/AMBER spectrum and visibilities
Gaussian models 2a (3.4?0.2) (1.99?0.24)
(?-2.2?m) mas Axial ratio 2b/2a 0.53
?0.03 Position angle PA 173 ? 9 Br? ? 2a
4.5?0.3 mas ??1.8 ?0.2 10-3 ?m
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Measured sizes of CPD-57 2874
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The close WRO system gamma2 Vel
P78 days,spectroscopic parameters well
constrained WR almost as bright as the O star in
K No dust!
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Can we resolve the WR star?
Not with baselines smaller than 100m in K
band, Better in H and very good in J
(He10830) We therefore expect a simple binary
signal
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O8IIIWC8 star TeffWC860000K TeffO8III30000K
Dfluxcont0.62 DfluxInt0.75
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Distance to be revised?
Hipparcos 25841-31 AMBER 36742-37
Petrov, R., Millour, F., Chesneau, O., et al.,
2006, submitted
To come study of the wind-wind collision (with
more data) confirmation of distance (with
much smaller error bars)
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Mass loss from evolved stars loss of spherical
sphericity II- Evolved small stars (cool)
Associated issues . Binarity, symbiotic
systems, . Planetary nebulae geometry, . Galactic
dust production, . Novae, supernovae Ia
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Massive AGB long pulsator OH26.50.6
Embedded object mJ17, mK8, mN-3!
P1559 days
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Complex objects . Many opacities ignored .
Dusty opacities, . Molecular opacities, .
Non-spherical geometry (always?), . Slow temporal
variability, About 140h of Ats observations
planned on OH/IR embedded sources! (PI Driebe
and Verhoelst)
Chesneau, O., Verhoelst, T., Lopez, B., et al.,
2005
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CPD-568032 and Hen2-113

• Central Stars De Marco et al. 97
• Late Wolf-Rayet WC10
• Teff 30000 K
• L 5000 Lo, dM/dt8-40 10-7Mo/yr
• Wind 160- 225 km.s-1
• Nebula Waters et al. 98, Cohen et al. 02, De
  Marco et al. 02
• Strong IR emission ? dust
• Edge-on disk suspected for CPD-568032
  (STIS/HST)
• Strong PAH emission, together with crystalline
  silicates features
• Double chemistry C (central star, hot disk)
  and O (cold disk ?)
• Distance 1.5 kpc
• Col A. Collioud (OCA,Fr), E. Lagadec (OCA, Fr),
  O. De Marco (AMNH, USA), A. Zijlstra (UMIST, UK),
  S. Wolf (MPIA, Ger), A. Acker (Obs Strasb., Fr),
  G. Clayton (LSU,USA), B. Lopez (OCA,Fr)

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HST
NACO

• Central source magnitude in L and M
  respectively 300 and 800 more luminous than any
  WR models!
• Central object resolved by NACO! FWHM155mas

Lagadec, E., Chesneau, O., Matsuura, M et al.,
2006
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CPD-56 dusty core a compact source
8.7 mm deconvolved image (30 PAHs)
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MIDI data on CPD-568032
CPD1 B45.7 m PA -5
CPD2 B45.6 m PA 5
CPD3 B41.2 m PA 51
N
CPD2
CPD1
Résolution36 mas à 8 µm60 mas à 13.5 µm
CPD3
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Best geometrical model for CPD-568032 ?
CPD1 B45.7 m PA -5
R 72 /- 3 mas(110 /- 5 UA)
N
i 29 /- 5
CPD2 B45.6 m PA 5
E
CPD3 B41.2 m PA 51
-15 /- 5
Good model ???
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Towards complex models
Shakura Sunyaev 1973 Wood et al. 2002,
Wolf 2005
a 2.0
h(100 UA)10 UA
ß 1.5
500AU
2000 AU
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Best model
10 micron image Résolution 13 mas par pixel
SED fit based on carbon chemistry only
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High-Resolution view of CPD-568032
10 mm image
8.7 mm image (30 PAHs)
Chesneau, O., Collioud, A., de Marco, O., et al.,
2006, submitted
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The connection between PNs/SNIa and symbiotic
systems recurrent novae
RS Oph is in outburst since the 13th of Feb.
2006 Last outburst January 1985! Estimated
distance 600pc (1.5-2.3kpc) DDT proposal (O.
Chesneau, C. Hummel, F. Millour, M.
Vannier) AMBER data taken the 18th of Feb.
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First data
Typical sizes continuum 3.5-4.5mas, Brg 6.5-9
mas (overresolved) Dynamics in Brg,
complex Object centro-symmetric in continuum
(fireball)
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Other objects QX Pup (OH231.84.2)
NACO 2.12
HST optical
HST Nicmos
NACO L band
Matsuura, M, Chesneau, O., Zijlstra, A et al.,
2006, in preparation
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MIDI spectrum
MIDI correlated flux
Typical extensions (Gaussian model)
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Actual situation . Papers are based on 2-6
visibility measurements only, . UT time
pressure, . ATs commissioning in progress, .
Limiting magnitude problems (no fringe
tracker) . Interesting science only with a
coupling with classical techniques (polarimetry,
spectroscopy, radio imaging) . The progress
will be slow . The VLTI is now almost
crystallized, . We have to learn and
understand the VLTI . Give access to broad
community, Success Only interferometer
worldwide offered in Open Time! . Pionnier in
extragalactic studies, mid-IR regime and high
spectral resolution,