An extended scattered light disk around AT Pyx

Astronomy and Astrophysics, vol. 662, pp. A74

Abstract

Aims. To understand how the multitude of planetary systems that have been discovered come to be, we need to study systems at different evolutionary stages, with different central stars but also in different environments. The most challenging environment for planet formation may be the harsh UV radiation field of nearby massive stars which quickly erodes disks by external photo-evaporation. We observed the AT Pyx system, located in the head of a cometary globule in the Gum Nebula, to search for signs of ongoing planet formation. Methods. We used the extreme adaptive optics imager VLT/SPHERE in Dual Beam Polarization Imaging Mode in H -band as well as in IRDIFS Extended mode ( K12 -band imaging and Y-H integral field spectroscopy) to observe AT Pyx in polarized light and total intensity. Additionally, we employed VLT/NACO to observe the system in the L -band. Results. We resolve the disk around AT Pyx for the first time in scattered light across multiple wavelengths in polarized light and total intensity. We find an extended (≥126 au) disk, with an intermediate inclination of between 35° and 42°. The disk shows a complex substructure and we identify two or possibly three spiral-like features. Depending on the precise geometry of the disk (which we cannot unambiguously infer from our data), the disk may be eccentric with an eccentricity of ~0.16 or partially self-shadowed. The spiral features and possible eccentricity are both consistent with signatures of an embedded gas giant planet with a mass of ~1 M Jup . Our own observations can rule out brown dwarf companions embedded in the resolved disk, but are nevertheless not sensitive enough to confirm or rule out the presence of a gas giant. Conclusions. AT Pyx is the first disk to be spatially resolved in a cometary globule in the Gum Nebula. By comparison with disks in the Orion Nebula Cluster we note that the extension of the disk may be exceptional for this environment if the external UV radiation field is indeed comparable to other cometary globules in the region. The signposts of ongoing planet formation are intriguing and need to be followed up with either higher sensitivity or at different wavelengths.

Authors 36

1. C. Ginski Aachen Leiden Observatory

   Leiden University · Leiden Observatory · University of Amsterdam

   Affiliation as printed

   Anton Pannekoek Institute for Astronomy, University of Amsterdam, Science Park 904, 1098XH Amsterdam, The Netherlands

   Leiden Observatory, Leiden University, 2300 RA Leiden, The Netherlands

2. R. Gratton

   Osservatorio Astronomico di Padova · National Institute for Astrophysics

   Affiliation as printed

   INAF – Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, 35122 Padova, Italy

   INAF – Osservatorio Astronomico di Padova, Vicolo dell'Osservatorio 5, 35122 Padova, Italy

3. Alexander J. Bohn Aachen Leiden Observatory

   Leiden University · Leiden Observatory

   Affiliation as printed

   Leiden Observatory, Leiden University, 2300 RA Leiden, The Netherlands

4. Carsten Dominik

   University of Amsterdam

   Affiliation as printed

   Anton Pannekoek Institute for Astronomy, University of Amsterdam, Science Park 904, 1098XH Amsterdam, The Netherlands

5. S. Jorquera

   Centre National de la Recherche Scientifique · University of Chile

   Affiliation as printed

   Unidad Mixta Internacional Franco-Chilena de Astronomía (CNRS, UMI 3386), Departamento de Astronomía, Universidad de Chile, Camino El Observatorio 1515, Las Condes, Santiago, Chile

6. G. Chauvin

   Centre National de la Recherche Scientifique · Institut de Planétologie et d'Astrophysique de Grenoble · University of Chile · Université Grenoble Alpes

   Affiliation as printed

   Unidad Mixta Internacional Franco-Chilena de Astronomía (CNRS, UMI 3386), Departamento de Astronomía, Universidad de Chile, Camino El Observatorio 1515, Las Condes, Santiago, Chile

   Univ. Grenoble Alpes, CNRS, IPAG, 38000 Grenoble, France

7. J. Milli

   Centre National de la Recherche Scientifique · Institut de Planétologie et d'Astrophysique de Grenoble · Université Grenoble Alpes

   Affiliation as printed

   Univ. Grenoble Alpes, CNRS, IPAG, 38000 Grenoble, France

8. M. Benisty

   Centre National de la Recherche Scientifique · Institut de Planétologie et d'Astrophysique de Grenoble · University of Chile · Université Grenoble Alpes

   Affiliation as printed

   Unidad Mixta Internacional Franco-Chilena de Astronomía (CNRS, UMI 3386), Departamento de Astronomía, Universidad de Chile, Camino El Observatorio 1515, Las Condes, Santiago, Chile

   Univ. Grenoble Alpes, CNRS, IPAG, 38000 Grenoble, France

9. R. Launhardt

   Max Planck Institute for Astronomy

   Affiliation as printed

   Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany

10. Ancla Müller

    Max Planck Institute for Astronomy

    Affiliation as printed

    Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany

11. Gabriele Cugno

    ETH Zurich · Institute for Particle Physics and Astrophysics

    Affiliation as printed

    Institute for Particle Physics and Astrophysics, ETH Zurich, Wolfgang-Pauli-Strasse 27, 8093 Zurich, Switzerland

12. R. G. van Holstein Aachen Leiden Observatory

    Leiden University · Leiden Observatory

    Affiliation as printed

    Leiden Observatory, Leiden University, 2300 RA Leiden, The Netherlands

13. Anthony Boccaletti

    Centre National de la Recherche Scientifique · Université Paris Sciences et Lettres · Observatoire de Paris · Sorbonne Université · Sorbonne Paris Cité · Laboratoire d’études spatiales et d’instrumentation en astrophysique

    Affiliation as printed

    LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Univ. Paris Diderot, Sorbonne Paris Cité, 5 place Jules Janssen, 92195 Meudon, France

14. G. A. Muro-Arena

    University of Amsterdam

    Affiliation as printed

    Anton Pannekoek Institute for Astronomy, University of Amsterdam, Science Park 904, 1098XH Amsterdam, The Netherlands

15. S. Desidera

    Osservatorio Astronomico di Padova · National Institute for Astrophysics

    Affiliation as printed

    INAF – Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, 35122 Padova, Italy

    INAF – Osservatorio Astronomico di Padova, Vicolo dell'Osservatorio 5, 35122 Padova, Italy

16. M. Keppler

    Max Planck Institute for Astronomy

    Affiliation as printed

    Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany

17. A. Zurlo

    Universidad Diego Portales

    Affiliation as printed

    Núcleo de Astronomía, Facultad de Ingeniería y Ciencias, Universidad Diego Portales, Av. Ejercito 441, Santiago, Chile

18. E. Sissa

    Osservatorio Astronomico di Padova · National Institute for Astrophysics

    Affiliation as printed

    INAF – Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, 35122 Padova, Italy

    INAF – Osservatorio Astronomico di Padova, Vicolo dell'Osservatorio 5, 35122 Padova, Italy

19. Thomas K. Henning

    Max Planck Institute for Astronomy

    Affiliation as printed

    Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany

20. M. Janson

    Stockholm University · Max Planck Institute for Astronomy

    Affiliation as printed

    Department of Astronomy, Stockholm University, 10691 Stockholm, Sweden

    Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany

21. M. Langlois

    Lyon 1 Université · École Normale Supérieure de Lyon · Centre National de la Recherche Scientifique · Université de Lyon · Aix-Marseille Université · Centre de Recherche Astrophysique de Lyon

    Affiliation as printed

    Aix Marseille Univ, CNRS, CNES, LAM, Marseille, France

    CRAL, CNRS, Université Lyon 1, Université de Lyon, ENS, 9 avenue Charles Andre, 69561 Saint Genis Laval, France

22. M. Bonnefoy

    Centre National de la Recherche Scientifique · Institut de Planétologie et d'Astrophysique de Grenoble · Université Grenoble Alpes

    Affiliation as printed

    Univ. Grenoble Alpes, CNRS, IPAG, 38000 Grenoble, France

23. F. Cantalloube

    Max Planck Institute for Astronomy

    Affiliation as printed

    Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany

24. Valentina D’Orazi

    Osservatorio Astronomico di Padova · National Institute for Astrophysics

    Affiliation as printed

    INAF – Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, 35122 Padova, Italy

    INAF – Osservatorio Astronomico di Padova, Vicolo dell'Osservatorio 5, 35122 Padova, Italy

25. M. Feldt

    Centre National de la Recherche Scientifique · Institut de Planétologie et d'Astrophysique de Grenoble · Université Grenoble Alpes

    Affiliation as printed

    Univ. Grenoble Alpes, CNRS, IPAG, 38000 Grenoble, France

26. J. Hagelberg

    University of Geneva

    Affiliation as printed

    Geneva Observatory, University of Geneva, Chemin des Maillettes 51, 1290 Sauverny, Switzerland

27. Damien Ségransan

    University of Geneva

    Affiliation as printed

    Geneva Observatory, University of Geneva, Chemin des Maillettes 51, 1290 Sauverny, Switzerland

28. A.‐M. Lagrange

    Centre National de la Recherche Scientifique · Institut de Planétologie et d'Astrophysique de Grenoble · Université Grenoble Alpes

    Affiliation as printed

    Univ. Grenoble Alpes, CNRS, IPAG, 38000 Grenoble, France

29. C. Lazzoni

    Osservatorio Astronomico di Padova · National Institute for Astrophysics

    Affiliation as printed

    INAF – Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, 35122 Padova, Italy

    INAF – Osservatorio Astronomico di Padova, Vicolo dell'Osservatorio 5, 35122 Padova, Italy

30. C. Romero

    Centre National de la Recherche Scientifique · Institut de Planétologie et d'Astrophysique de Grenoble · Université Grenoble Alpes

    Affiliation as printed

    Univ. Grenoble Alpes, CNRS, IPAG, 38000 Grenoble, France

31. Tobias O. B. Schmidt

    Centre National de la Recherche Scientifique · Universität Hamburg · Université Paris Sciences et Lettres · Observatoire de Paris · Sorbonne Université · Sorbonne Paris Cité · Laboratoire d’études spatiales et d’instrumentation en astrophysique

    Affiliation as printed

    Hamburger Sternwarte, Gojenbergsweg 112, 21029 Hamburg, Germany

    LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Univ. Paris Diderot, Sorbonne Paris Cité, 5 place Jules Janssen, 92195 Meudon, France

32. A. Vigan

    Centre National de la Recherche Scientifique · Aix-Marseille Université

    Affiliation as printed

    Aix Marseille Univ, CNRS, CNES, LAM, Marseille, France

33. C. Petit

    Université Paris-Saclay · Office National d'Études et de Recherches Aérospatiales · Département Optique et Techniques Associées

    Affiliation as printed

    DOTA, ONERA, Université Paris Saclay, 91123, Palaiseau France

34. R. Roelfsema
    Affiliation as printed

    NOVA Optical Infrared Instrumentation Group, Oude Hoogeveensedijk 4, 7991 PD Dwingeloo, The Netherlands

35. Johan H. Pragt
    Affiliation as printed

    NOVA Optical Infrared Instrumentation Group, Oude Hoogeveensedijk 4, 7991 PD Dwingeloo, The Netherlands

36. Luc Weber

    University of Geneva

    Affiliation as printed

    Geneva Observatory, University of Geneva, Chemin des Maillettes 51, 1290 Sauverny, Switzerland