SOLIS

Astronomy and Astrophysics, vol. 662, pp. A104

Abstract

Context.Protostellar jets are an important agent of star formation feedback, tightly connected with the mass-accretion process. The history of jet formation and mass ejection provides constraints on the mass accretion history and on the nature of the driving source. Aims.We characterize the time-variability of the mass-ejection phenomena at work in the class 0 protostellar phase in order to better understand the dynamics of the outflowing gas and bring more constraints on the origin of the jet chemical composition and the mass-accretion history. Methods.Using the NOrthern Extended Millimeter Array (NOEMA) interferometer, we have observed the emission of the CO 2–1 and SONJ= 54–43rotational transitions at an angular resolution of 1.0″ (820 au) and 0.4″ (330 au), respectively, toward the intermediate-mass class 0 protostellar system Cep E. Results.The CO high-velocity jet emission reveals a central component of ≤400 au diameter associated with high-velocity molecular knots that is also detected in SO, surrounded by a collimated layer of entrained gas. The gas layer appears to be accelerated along the main axis over a length scaleδ0~ 700 au, while its diameter gradually increases up to several 1000 au at 2000 au from the protostar. The jet is fragmented into 18 knots of mass ~10−3M⊙, unevenly distributed between the northern and southern lobes, with velocity variations up to 15 km s−1close to the protostar. This is well below the jet terminal velocities in the northern (+ 65 km s−1) and southern (−125 km s−1) lobes. The knot interval distribution is approximately bimodal on a timescale of ~50–80 yr, which is close to the jet-driving protostar Cep E-A and ~150–20 yr at larger distances >12″. The mass-loss rates derived from knot masses are steady overall, with values of 2.7 × 10−5M⊙yr−1and 8.9 × 10−6M⊙yr−1in the northern and southern lobe, respectively. Conclusions.The interaction of the ambient protostellar material with high-velocity knots drives the formation of a molecular layer around the jet. This accounts for the higher mass-loss rate in the northern lobe. The jet dynamics are well accounted for by a simple precession model with a period of 2000 yr and a mass-ejection period of 55 yr.

Authors 48

1. A. de A. Schutzer

   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

2. P. R. Rivera-Ortíz

   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

3. Bertrand Lefloch

   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

4. Antoine Gusdorf

   Centre National de la Recherche Scientifique · Université Paris Sciences et Lettres · Observatoire de Paris · École Normale Supérieure - PSL · Sorbonne Université · Laboratoire d’Etudes du Rayonnement et de la Matière en Astrophysique et Atmosphères · Laboratoire de Physique de l'Ecole Normale Supérieure

   Affiliation as printed

   Laboratoire de Physique de l’ENS, ENS, Université PSL, CNRS, Sorbonne Université, Université de Paris, 75005 Paris, France

   Observatoire de Paris, PSL University, Sorbonne Université, LERMA, 75014 Paris, France

5. Cécile Favre

   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

6. Dominique M. Segura-Cox

   Max Planck Institute for Extraterrestrial Physics · The University of Texas at Austin

   Affiliation as printed

   Department of Astronomy, The University of Texas at Austin, 2500 Speedway, Austin, TX 78712, USA

   Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, 85748 Garching, Germany

7. Ana López-Sepulcre

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

   Affiliation as printed

   Institut de Radioastronomie Millimétrique (IRAM), 300 rue de la Piscine, 38406 Saint-Martin-D’Hères, France

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

8. R. Neri

   Institut de Radioastronomie Millimétrique

   Affiliation as printed

   Institut de Radioastronomie Millimétrique (IRAM), 300 rue de la Piscine, 38406 Saint-Martin-D’Hères, France

9. Juan Ospina-Zamudio

   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

10. M. De Simone

    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

11. C. Codella

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

    Affiliation as printed

    INAF, Osservatorio Astrofísico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy

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

12. S. Viti Aachen Leiden Observatory

    Leiden University · Leiden Observatory · University College London

    Affiliation as printed

    Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK

    Leiden Observatory, Leiden University, PO Box 9513, 2300 RA Leiden, The Netherlands

13. L. Podio

    Arcetri Astrophysical Observatory

    Affiliation as printed

    INAF, Osservatorio Astrofísico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy

14. Jaime E. Pineda

    Max Planck Institute for Extraterrestrial Physics

    Affiliation as printed

    Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, 85748 Garching, Germany

15. Ross O’Donoghue

    University College London

    Affiliation as printed

    Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK

16. Cecilia Ceccarelli

    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

17. P. Caselli

    Max Planck Institute for Extraterrestrial Physics

    Affiliation as printed

    Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, 85748 Garching, Germany

18. F. O. Alves

    Max Planck Institute for Extraterrestrial Physics

    Affiliation as printed

    Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, 85748 Garching, Germany

19. R. Bachiller

    Spanish National Observatory

    Affiliation as printed

    IGN, Observatorio Astronómico Nacional, Calle Alfonso XII, 28004 Madrid, Spain

20. Nadia Balucani

    Centre National de la Recherche Scientifique · University of Perugia · Arcetri Astrophysical Observatory · Institut de Planétologie et d'Astrophysique de Grenoble · Université Grenoble Alpes

    Affiliation as printed

    Dipartimento di Chimica, Biologia e Biotecnologie, Via Elce di Sotto 8, 06123 Perugia, Italy

    INAF, Osservatorio Astrofísico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy

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

21. E. Bianchi

    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

22. Luca Bizzocchi

    Max Planck Institute for Extraterrestrial Physics · University of Bologna

    Affiliation as printed

    Dipartimento di Chimica “G. Ciamician” via F. Selmi 2, 40126 Bologna, Italy

    Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, 85748 Garching, Germany

23. S. Bottinelli

    Centre National de la Recherche Scientifique · Université Toulouse III - Paul Sabatier · Institut de Recherche en Astrophysique et Planétologie · Université de Toulouse

    Affiliation as printed

    CNRS, IRAP, 9 Av. Colonel Roche, BP 44346, 31028 Toulouse Cedex 4, France

    Université de Toulouse, UPS-OMP, IRAP, Toulouse, France

24. E. Caux

    Université Toulouse III - Paul Sabatier · Institut de Recherche en Astrophysique et Planétologie · Université de Toulouse

    Affiliation as printed

    Université de Toulouse, UPS-OMP, IRAP, Toulouse, France

25. A. Chacón-Tanarro

    Spanish National Observatory

    Affiliation as printed

    IGN, Observatorio Astronómico Nacional, Calle Alfonso XII, 28004 Madrid, Spain

26. F. Dulieu

    Centre National de la Recherche Scientifique · Université Paris Sciences et Lettres · Observatoire de Paris · Sorbonne Université · Laboratoire d’Etudes du Rayonnement et de la Matière en Astrophysique et Atmosphères · Université de Cergy-Pontoise

    Affiliation as printed

    LERMA, Université de Cergy-Pontoise, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Université, UPMC, Univ. Paris 06, 95000 Cergy Pontoise, France

27. Joan Enrique-Romero

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

    Affiliation as printed

    Departament de Química, Universitat Autónoma de Barcelona, 08193 Bellaterra, Catalonia, Spain

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

28. F. Fontani

    Arcetri Astrophysical Observatory

    Affiliation as printed

    INAF, Osservatorio Astrofísico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy

29. Siyi Feng

    Max Planck Institute for Extraterrestrial Physics

    Affiliation as printed

    Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, 85748 Garching, Germany

30. Jonathan Holdship Aachen Leiden Observatory

    Leiden University · Leiden Observatory · University College London

    Affiliation as printed

    Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK

    Leiden Observatory, Leiden University, PO Box 9513, 2300 RA Leiden, The Netherlands

31. Izaskun Jiménez-Serra

    Centro de Astrobiología

    Affiliation as printed

    Centro de Astrobiología (CSIC, INTA), Ctra. de Ajalvir, km. 4, Torrejón de Ardoz, 28850 Madrid, Spain

32. A. Jaber Al-Edhari

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

    Affiliation as printed

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

    University of AL-Muthanna, College of Science, Physics Department, AL-Muthanna, Iraq

33. C. Kahane

    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

34. Valerio Lattanzi

    Max Planck Institute for Extraterrestrial Physics

    Affiliation as printed

    Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, 85748 Garching, Germany

35. Yoko Oya

    The University of Tokyo

    Affiliation as printed

    Department of Physics, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan

36. Anna F. Punanova

    Ural Federal University

    Affiliation as printed

    Ural Federal University, 620002, 19 Mira street, Yekaterinburg, Russia

37. Albert Rimola

    Universitat Autònoma de Barcelona

    Affiliation as printed

    Departament de Química, Universitat Autónoma de Barcelona, 08193 Bellaterra, Catalonia, Spain

38. Nami Sakai

    RIKEN

    Affiliation as printed

    The Institute of Physical and Chemical Research (RIKEN), 2-1, Hirosawa, Wako-shi, Saitama 351-0198, Japan

39. S. Spezzano

    Max Planck Institute for Extraterrestrial Physics

    Affiliation as printed

    Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, 85748 Garching, Germany

40. Ian R. Sims

    Centre National de la Recherche Scientifique · Institut de Physique de Rennes · Université de Rennes

    Affiliation as printed

    Univ. Rennes, CNRS, IPR (Institut de Physique de Rennes) – UMR 6251, 35000 Rennes, France

41. V. Taquet

    Arcetri Astrophysical Observatory

    Affiliation as printed

    INAF, Osservatorio Astrofísico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy

42. L. Testi

    European Southern Observatory · Arcetri Astrophysical Observatory

    Affiliation as printed

    ESO, Karl Schwarzchild Srt. 2, 85478 Garching bei München, Germany

    INAF, Osservatorio Astrofísico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy

43. P. Theulé

    Centre National de la Recherche Scientifique · Aix-Marseille Université · Physique des interactions ioniques et moléculaires

    Affiliation as printed

    Aix-Marseille Université, PIIM UMR-CNRS 7345, 13397 Marseille, France

44. Piero Ugliengo

    University of Turin

    Affiliation as printed

    Università degli Studi di Torino, Dipartimento Chimica Via Pietro Giuria 7, 10125 Torino, Italy

45. C. Vastel

    Centre National de la Recherche Scientifique · Université Toulouse III - Paul Sabatier · Institut de Recherche en Astrophysique et Planétologie · Université de Toulouse

    Affiliation as printed

    CNRS, IRAP, 9 Av. Colonel Roche, BP 44346, 31028 Toulouse Cedex 4, France

    Université de Toulouse, UPS-OMP, IRAP, Toulouse, France

46. Anton I. Vasyunin

    Ural Federal University

    Affiliation as printed

    Ural Federal University, 620002, 19 Mira street, Yekaterinburg, Russia

47. Fanny Vazart

    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

48. S. Yamamoto

    The University of Tokyo

    Affiliation as printed

    Department of Physics, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan