Protoplanetary%20worlds%20at%20the%20AU%20scale

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Protoplanetary worlds at the AU scale

• Jean Philippe Berger
• J. Monnier, R. Millan-Gabet, W. Traub, M.
  Benisty, F. Malbet, E. Pedretti

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Outline

• A young stars environment
• The contribution of two telescope broadband
  infrared interferometry to the knowledge of disk
  structure
• First steps towards imaging
• Conclusion

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A young stars environment
Infrared excess
Optical(HubbleAO) /mm imaging
Presence of a flared disk of gas and dust
associated with bipolar mass loss winds and/or
highly collimated jets, Typical disk sizes
50-1000AU.
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The standard disk model
e.g. Malbet Bertout (1995, AAS 113, 369)

• Optically thick disk both for inner gas and
  outer dust
• Simple power-law temperature distribution (T a
  r-0.75, T a r-0.5)
• Oblique disk heating
• -gt fits rather well spectral energy
  distributions (SEDs)

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2001 important revision of the model
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2T interferometry the near-IR view

• PTI, IOTA and Keck have played a major role in
  near infrared YSO observing during (Malbet
  Berger 98, Millan-Gabet 2001,Akeson2000,02
  Eisner2002,2004, Monnier)
• Authors concluded Herbig AeBe and T Tauri
  estimated sizes often bigger than predicted with
  standard disk model.
• Signs for disk flattening at the astronomical
  unit scale.

Eisner, 2004
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2T interferometry the near-IR view
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2T interferometry the near-IR view

1. Evidence for inner rim (Muzerolle 2004)
2. Flared disk can account for some estimated sizes
   (Lachaume 2003)
3. Fu Orionis stars observations compatible with
   standard models provided renmant envelopes or
   putative companions are taken into account
   (Malbet 2005, Millan-Gabet 20050

TTauris
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2T interferometry the near-IR view

1. Some visibilities observations are compatible
   with standard disk (Malbet, 2005)
2. Evolutionary status of these stars should be
   debated (Monnier 2006)

Herbig Be Stars
Wind
Disk
Disk
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2T interferometry the near-IR view
Presence of resolved Flux (halo, envelop renmant)
IntrinsicVariability
Visibility modelling is highly sensitive To the
knowledge of short baseline incohernet Flux and
stellar vs. disk emission ratio
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2T interferometry the midIR view
Flaring
Sizes consistent with flat self-shadowed /
flaring disk model SED classification
Sizes consistent with flat self-shadowed /
flaring disk model SED classification
Self-shadowed
Leinert et al. (2004, AA, 423, 537)
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First steps towards imaging
Isella et al 2005

• This IONIC3/IOTA campaign was aimed at surveying
  the brightest HerbigAeBe and Ttauri stars in
  search for any asymetry (departure from zero
  closure phase) at the astronomical unit scale in
  order to select candidates for imaging.
• Both a flared disk and disk with inner rim
  generate asymetries.

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First steps towards imaging

• This IONIC3/IOTA campaign was aimed at surveying
  the brightest HerbigAeBe and Ttauri stars in
  search for any asymetry (departure from zero
  closure phase) at the astronomical unit scale in
  order to select candidates for imaging.
• Both a flared disk and disk with inner rim
  generate asymetries.

Malbet 2001
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(No Transcript)
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Results

• Essentially zero closure phases
• Evidence for resolved flux (incoherent)?

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Interpretation in the inner rim context
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Interpretation in the inner rim context
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Parametric imaging
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Direct imaging
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Imaging protoplanetary disks

• Imaging the inner AU requires a lot of telescopes
  and (preferably than) or a lot of array
  configurations
• Model ambiguities often vanish at longer
  baselines
• YSO short baselines images (i.e AO), are
  essential.
• Simultaneous photometry is very important
• Understanding the disk structure would ideally
  require joint near and mid-infrared observations
• Second generation VLTI instrumentation is more
  than welcome.

IOTA3 _at_ H
Keck-I _at_ K
CHARA _at_ K 260 m baseline!