Flows of gas through a protoplanetary gap

Journal name:
Nature
Volume:
493,
Pages:
191–194
Date published:
DOI:
doi:10.1038/nature11769
Received
Accepted
Published online
Corrected online

The formation of gaseous giant planets is thought to occur in the first few million years after stellar birth. Models1 predict that the process produces a deep gap in the dust component (shallower in the gas2, 3, 4). Infrared observations of the disk around the young star HD142527 (at a distance of about 140 parsecs from Earth) found an inner disk about 10 astronomical units (au) in radius5 (1au is the Earth–Sun distance), surrounded by a particularly large gap6 and a disrupted7 outer disk beyond 140au. This disruption is indicative of a perturbing planetary-mass body at about 90au. Radio observations8, 9 indicate that the bulk mass is molecular and lies in the outer disk, whose continuum emission has a horseshoe morphology8. The high stellar accretion rate10 would deplete the inner disk11 in less than one year, and to sustain the observed accretion matter must therefore flow from the outer disk and cross the gap. In dynamical models, the putative protoplanets channel outer-disk material into gap-crossing bridges that feed stellar accretion through the inner disk12. Here we report observations of diffuse CO gas inside the gap, with denser HCO+ gas along gap-crossing filaments. The estimated flow rate of the gas is in the range of 7×10−9 to 2×10−7 solar masses per year, which is sufficient to maintain accretion onto the star at the present rate.

Change history

Corrected online 09 January 2013
An affiliation and a figure citation were corrected.

References

  1. Lubow, S. H. & D’Angelo, G. Gas flow across gaps in protoplanetary disks. Astrophys. J. 641, 526533 (2006)
  2. Fouchet, L., Gonzalez, J.-F. & Maddison, S. T. Planet gaps in the dust layer of 3D protoplanetary disks. I. Hydrodynamical simulations of T Tauri disks. Astron. Astrophys. 518, A16 (2010)
  3. Ayliffe, B. A., Laibe, G., Price, D. J. & Bate, M. R. On the accumulation of planetesimals near disc gaps created by protoplanets. Mon. Not. R. Astron. Soc. 423, 14501462 (2012)
  4. Zhu, Z., Nelson, R. P., Hartmann, L., Espaillat, C. & Calvet, N. Transitional and pretransitional disks: gap opening by multiple planets? Astrophys. J. 729, 4758 (2011)
  5. van Boekel, R. et al. The building blocks of planets within the ‘terrestrial’ region of protoplanetary disks. Nature 432, 479482 (2004)
  6. Fukagawa, M. et al. Near-infrared images of protoplanetary disk surrounding HD 142527. Astrophys. J. 636, L153L156 (2006)
  7. Casassus, S. et al. The dynamically disrupted gap in HD 142527. Astrophys. J. 754, L31L35 (2012)
  8. Ohashi, N. Observational signature of planet formation: the ALMA view. Astrophys. Space Sci. 313, 101107 (2008)
  9. Öberg, K. I. et al. Disk imaging survey of chemistry with SMA. II. Southern sky protoplanetary disk data and full sample statistics. Astrophys. J. 734, 98109 (2011)
  10. Garcia Lopez, R., Natta, A., Testi, L. & Habart, E. Accretion rates in Herbig Ae stars. Astron. Astrophys. 459, 837842 (2006)
  11. Verhoeff, A. P. et al. The complex circumstellar environment of HD 142527. Astron. Astrophys. 528, A91A103 (2011)
  12. Dodson-Robinson, S. E. & Salyk, C. Transitional disks as signposts of young, multiplanet systems. Astrophys. J. 738, 131145 (2011)
  13. Fujiwara, H. et al. The asymmetric thermal emission of the protoplanetary disk surrounding HD 142527 seen by Subaru/COMICS. Astrophys. J. 644, L133L136 (2006)
  14. Lyo, A.-R., Ohashi, N., Qi, C., Wilner, D. J. & Su, Y.-N. Millimeter observations of the transition disk around HD 135344B (SAO 206462). Astron. J. 142, 151160 (2011)
  15. Mathews, G. S., Williams, J. P. & Ménard, F. 880µm imaging of a transitional disk in Upper Scorpius: holdover from the era of giant planet formation? Astrophys. J. 753, 5970 (2012)
  16. Tatulli, E. et al. Constraining the wind launching region in Herbig Ae stars: AMBER/VLTI spectroscopy of HD 104237. Astron. Astrophys. 464, 5558 (2007)
  17. Kraus, S. et al. The origin of hydrogen line emission for five Herbig Ae/Be stars spatially resolved by VLTI/AMBER spectro-interferometry. Astron. Astrophys. 489, 11571173 (2008)
  18. Eisner, J. A. et al. Spatially and spectrally resolved hydrogen gas within 0.1 AU of T Tauri and Herbig Ae/Be Stars. Astrophys. J. 718, 774794 (2010)
  19. Carr, J. S., Mathieu, R. D. & Najita, J. R. Evidence for residual material in accretion disk gaps: CO fundamental emission from the T Tauri spectroscopic binary DQ Tauri. Astrophys. J. 551, 454460 (2001)
  20. Najita, J., Carr, J. S. & Mathieu, R. D. Gas in the terrestrial planet region of disks: CO fundamental emission from T Tauri Stars. Astrophys. J. 589, 931952 (2003)
  21. Acke, B. & van den Ancker, M. E. Resolving the disk rotation of HD 97048 and HD 100546 in the [O I] 6300 Å line: evidence for a giant planet orbiting HD 100546. Astron. Astrophys. 449, 267279 (2006)
  22. van der Plas, G. et al. The structure of protoplanetary disks surrounding three young intermediate mass stars. I. Resolving the disk rotation in the [OI] 6300 Å line. Astron. Astrophys. 485, 487495 (2008)
  23. Salyk, C., Blake, G. A., Boogert, A. C. A. & Brown, J. M. High-resolution 5µm spectroscopy of transitional disks. Astrophys. J. 699, 330347 (2009)
  24. Pontoppidan, K. M. et al. Spectroastrometric imaging of molecular gas within protoplanetary disk gaps. Astrophys. J. 684, 13231329 (2008)
  25. van der Plas, G. et al. Evidence for CO depletion in the inner regions of gas-rich protoplanetary disks. Astron. Astrophys. 500, 11371141 (2009)
  26. Pontoppidan, K. M., Blake, G. A. & Smette, A. The structure and dynamics of molecular gas in planet-forming zones: a CRIRES spectro-astrometric survey. Astrophys. J. 733, 84100 (2011)
  27. Sacco, G. G. et al. High-resolution Spectroscopy of Ne II emission from young stellar objects. Astrophys. J. 747, 142 (2012)
  28. Piétu, V., Gueth, F., Hily-Blant, P., Schuster, K.-F. & Pety, J. High resolution imaging of the GG Tauri system at 267 GHz. Astron. Astrophys. 528, A81A95 (2011)
  29. Beck, T. L. et al. Circumbinary gas accretion onto a central binary: infrared molecular hydrogen emission from GG Tau A. Astrophys. J. 754, 7277 (2012)
  30. Regály, Z., Juhász, A., Sándor, Z. & Dullemond, C. P. Possible planet-forming regions on submillimetre images. Mon. Not. R. Astron. Soc. 419, 17011712 (2012)

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Author information

Affiliations

  1. Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago, Chile

    • Simon Casassus,
    • Gerrit van der Plas,
    • Sebastian Perez M &
    • Vachail Salinas
  2. Joint ALMA Observatory, Alonso de Córdova 3107, Vitacura 763-0355, Santiago, Chile

    • William R. F. Dent &
    • Antonio Hales
  3. European Southern Observatory, Casilla 19001, Vitacura, Santiago, Chile

    • William R. F. Dent,
    • Dimitri Mawet &
    • Julien H. Girard
  4. National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, Virginia 22903-2475, USA

    • Ed Fomalont,
    • Antonio Hales &
    • Al Wootten
  5. Observatoire de Genève, Université de Genève, 51 Chemin des Maillettes, 1290, Versoix, Switzerland

    • Janis Hagelberg
  6. Departamento de Astronomía y Astrofísica, Pontificia Universidad Católica de Chile, Santiago, Chile

    • Andrés Jordán
  7. UMI-FCA, CNRS/INSU France (UMI 3386), and Departamento de Astronomía, Universidad de Chile, Santiago, Chile

    • Francois Ménard
  8. CNRS/UJF Grenoble 1, UMR 5274, Institut de Planétologie et dAstrophysique de Grenoble (IPAG), F-48041 Grenoble Cedex 9, France

    • Francois Ménard
  9. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, USA

    • David Wilner
  10. Department of Astronomy, UC Berkeley, 601 Campbell Hall, Berkeley, California 94720, USA

    • A. Meredith Hughes
  11. Departamento de Física y Astronomía, Universidad Valparaiso, Avenida Gran Bretana 1111, Valparaiso, Chile

    • Matthias R. Schreiber &
    • Hector Canovas
  12. University Observatory, Ludwig-Maximillians University, D-81679 Munich, Germany

    • Barbara Ercolano
  13. Center of Mathematical Modeling, University of Chile, Avenida Blanco Encalada 2120 Piso 7, Santiago, Chile

    • Pablo E. Román

Contributions

General design of ALMA project, data analysis and write-up: S.C. Discussion of infrared observations of gas in cavities: G.v.d.P. Hydrodynamical modelling: S.P.M. ALMA data reduction: A.H. and E.F. Infrared-image processing: D.M., J.H. and J.H.G. Contributions to ALMA Cycle 0 proposal: A.J., F.M., D.W. and A.M.H. Design of ALMA observations: A.W., A.H. and S.C. Authors W.R.F.D. to A.W. contributed equally. All authors discussed the results and commented on the manuscript.

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The authors declare no competing financial interests.

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    This file contains Supplementary Text and Data 1-5, Supplementary References and Supplementary Figures 1-13.

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