37 new validated planets in overlapping K2 campaigns

Monthly Notices of the Royal Astronomical Society, vol. 508, pp. 195–218

Abstract

ABSTRACT We analysed 68 candidate planetary systems first identified during Campaigns 5 and 6 (C5 and C6) of the NASA K2 mission. We set out to validate these systems by using a suite of follow-up observations, including adaptive optics, speckle imaging, and reconnaissance spectroscopy. The overlap between C5 with C16 and C18, and C6 with C17, yields light curves with long baselines that allow us to measure the transit ephemeris very precisely, revisit single transit candidates identified in earlier campaigns, and search for additional transiting planets with longer periods not detectable in previous works. Using vespa, we compute false positive probabilities of less than 1 per cent for 37 candidates orbiting 29 unique host stars and hence statistically validate them as planets. These planets have a typical size of 2.2 R⊕ and orbital periods between 1.99 and 52.71 d. We highlight interesting systems including a sub-Neptune with the longest period detected by K2, sub-Saturns around F stars, several multiplanetary systems in a variety of architectures. These results show that a wealth of planetary systems still remains in the K2 data, some of which can be validated using minimal follow-up observations and taking advantage of analyses presented in previous catalogues.

Authors 25

1. John H. Livingston

   The University of Tokyo

   Affiliation as printed

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

2. Michael Endl

   The University of Texas at Austin

   Affiliation as printed

   Department of Astronomy and McDonald Observatory, University of Texas at Austin , 2515 Speedway, Stop C1400, Austin TX 78712, USA

3. William D. Cochran

   The University of Texas at Austin

   Affiliation as printed

   Center for Planetary Systems Habitability, The University of Texas at Austin , 2305 Speedway Stop C1160, Austin, TX 78712-1692, USA

   Department of Astronomy and McDonald Observatory, University of Texas at Austin , 2515 Speedway, Stop C1400, Austin TX 78712, USA

4. Teruyuki Hirano

   Tokyo Institute of Technology

   Affiliation as printed

   Department of Earth and Planetary Sciences, Tokyo Institute of Technology , 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8551, Japan

5. Rafael A. García

   Centre National de la Recherche Scientifique · Commissariat à l'Énergie Atomique et aux Énergies Alternatives · Université Paris-Saclay · Astrophysique, Instrumentation et Modélisation · Sorbonne Paris Cité · Université Paris Diderot

   Affiliation as printed

   AIM, CEA, CNRS, Université Paris-Saclay, Université Paris Diderot , Sorbonne Paris Cité, F-91191 Gif-sur-Yvette, France

6. S. Mathur

   Universidad de La Laguna · Instituto de Astrofísica de Canarias

   Affiliation as printed

   Departamento de Astrofísica, Universidad de La Laguna , Tenerife, La Laguna E-38206, Spain

   Instituto de Astrofísica de Canarias (IAC) , Tenerife, La Laguna E-38205, Spain

7. Kristine W. F. Lam

   Technische Universität Berlin

   Affiliation as printed

   Center for Astronomy and Astrophysics, Technical University Berlin , Hardenbergstr. 36, Berlin D-10623, Germany

8. J. Korth

   Chalmers University of Technology

   Affiliation as printed

   Department of Space, Earth and Environment, Astronomy and Plasma Physics, Chalmers University of Technology , Gothenburg SE-412 96, Sweden

9. Alessandro Alberto Trani

   The University of Tokyo

   Affiliation as printed

   Department of Earth Science and Astronomy, College of Arts and Sciences, University of Tokyo , 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan

10. F. Dai

    California Institute of Technology

    Affiliation as printed

    Division of Geological and Planetary Sciences, California Institute of Technology , 1200 East California Blvd, Pasadena CA 91125, USA

11. E. Díez-Alonso
    Affiliation as printed

    Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias (ICTEA) , C.Independencia 13, E-33004, Spain

12. A. Castro-González
    Affiliation as printed

    Instituto Universitario de Ciencias y Tecnologías Espaciales de Asturias (ICTEA) , C.Independencia 13, E-33004, Spain

13. Malcolm C. Fridlund Aachen Leiden Observatory

    Leiden University · Leiden Observatory · Chalmers University of Technology

    Affiliation as printed

    Leiden Observatory, Leiden University , Leiden NL-2333CA, the Netherlands

    Onsala Space Observatory, Department of Space, Earth and Environment, Chalmers University of Technology , Onsala SE-439 92, Sweden

14. Akihiko Fukui

    Instituto de Astrofísica de Canarias · The University of Tokyo

    Affiliation as printed

    Instituto de Astrofísica de Canarias (IAC) , Tenerife, La Laguna E-38205, Spain

    Komaba Institute for Science, The University of Tokyo , 3-8-1 Komaba, Meguro, Tokyo 153-8902, Japan

15. D. Gandolfi

    University of Turin

    Affiliation as printed

    Dipartimento di Fisica, Universitá di Torino , Via P. Giuria 1, Torino I-10125, Italy

16. P. Kábath

    Czech Academy of Sciences · Czech Academy of Sciences, Astronomical Institute

    Affiliation as printed

    Astronomical Institute, Czech Academy of Sciences , Fricova 298, Ondrejov CZ-25165, Czech Republic

17. Masayuki Kuzuhara

    California Institute of Technology

    Affiliation as printed

    Division of Geological and Planetary Sciences, California Institute of Technology , 1200 East California Blvd, Pasadena CA 91125, USA

18. R. Luque

    Universidad de La Laguna · Instituto de Astrofísica de Canarias

    Affiliation as printed

    Departamento de Astrofísica, Universidad de La Laguna , Tenerife, La Laguna E-38206, Spain

    Instituto de Astrofísica de Canarias (IAC) , Tenerife, La Laguna E-38205, Spain

19. Arjun B. Savel

    University of Maryland, College Park

    Affiliation as printed

    Department of Astronomy, University of Maryland , College Park, College Park MD 20742 USA

20. Holden Gill

    University of California, Berkeley

    Affiliation as printed

    Department of Astronomy, University of California Berkeley , Berkeley CA 94720, USA

21. Courtney D. Dressing

    University of California, Berkeley

    Affiliation as printed

    Department of Astronomy, University of California Berkeley , Berkeley CA 94720, USA

22. Steven Giacalone

    University of California, Berkeley

    Affiliation as printed

    Department of Astronomy, University of California Berkeley , Berkeley CA 94720, USA

23. Norio Narita

    Japan Science and Technology Agency · Astrobiology Center · Instituto de Astrofísica de Canarias · The University of Tokyo

    Affiliation as printed

    Astrobiology Center , 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan

    Instituto de Astrofísica de Canarias (IAC) , Tenerife, La Laguna E-38205, Spain

    Japan Science and Technology Agency , PRESTO, 3-8-1 Komaba, Meguro, Tokyo 153-8902, Japan

    Komaba Institute for Science, The University of Tokyo , 3-8-1 Komaba, Meguro, Tokyo 153-8902, Japan

24. Ε. Πάλλη

    Universidad de La Laguna · Instituto de Astrofísica de Canarias

    Affiliation as printed

    Departamento de Astrofísica, Universidad de La Laguna , Tenerife, La Laguna E-38206, Spain

    Instituto de Astrofísica de Canarias (IAC) , Tenerife, La Laguna E-38205, Spain

25. Motohide Tamura

    Astrobiology Center · National Astronomical Observatory of Japan · The University of Tokyo

    Affiliation as printed

    Astrobiology Center , 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan

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

    National Astronomical Observatory of Japan , 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan