Exo-planets; High-precision; Host-stars; Neptune; Photometric measurements; Photometrics; Planet finders; Radial velocity datum; Radial-velocity observations; Satellite mission; Astronomy and Astrophysics; Space and Planetary Science; astro-ph.EP
Abstract :
[en] We present the discovery and characterization of a transiting sub-Neptune that orbits the nearby (28 pc) and bright (V = 8.37) K0V star HD 207897 (TOI-1611) with a 16.20-day period. This discovery is based on photometric measurements from the Transiting Exoplanet Survey Satellite mission and radial velocity (RV) observations from the SOPHIE, Automated Planet Finder, and HIRES high-precision spectrographs. We used EXOFASTv2 to model the parameters of the planet and its host star simultaneously, combining photometric and RV data to determine the planetary system parameters. We show that the planet has a radius of 2.50 ± 0.08 RE and a mass of either 14.4 ± 1.6 ME or 15.9 ± 1.6 ME with nearly equal probability. The two solutions correspond to two possibilities for the stellar activity period. The density accordingly is either 5.1 ± 0.7 g cm3 or 5.50.7+0.8 g cm3, making it one of the relatively rare dense sub-Neptunes. The existence of this dense planet at only 0.12 AU from its host star is unusual in the currently observed sub-Neptune (2 < RE < 4) population. The most likely scenario is that this planet has migrated to its current position.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Heidari, N.; Department of Physics, Shahid Beheshti University, Tehran, Iran ; Laboratoire J.-L. Lagrange, Observatoire de la Côte DAzur (OCA), Universite de Nice-Sophia Antipolis (UNS), CNRS, Nice Cedex 2, France ; Aix Marseille Univ, CNRS, CNES, LAM, Marseille, France
Boisse, I.; Aix Marseille Univ, CNRS, CNES, LAM, Marseille, France
Orell-Miquel, J.; Instituto de Astrofísica de Canarias, La Laguna, Spain ; Departamento de Astrofísica, Universidad de la Laguna, La Laguna, Spain
Hébrard, G.; Observatoire de Haute-Provence, CNRS, Université D’Aix-Marseille, France ; Institut D’astrophysique de Paris, UMR 7095 CNRS, Université Pierre et Marie Curie, Paris, France
Acuña, L.; Aix Marseille Univ, CNRS, CNES, LAM, Marseille, France
Hara, N.C.; Observatoire de Genève, Université de Genève, Sauverny, Switzerland
Lillo-Box, J.; Centro de Astrobiologiá (CAB CSIC-INTA), Depto. de Astrofísica, ESAC Campus, Spain
Eastman, J.D.; Center for Astrophysics | Harvard and Smithsonian, Cambridge, United States
Arnold, L.; Observatoire de Haute-Provence, CNRS, Université D’Aix-Marseille, France ; Canada France Hawaii Telescope Corporation (CFHT), Kamuela, United States
Astudillo-Defru, N.; Departamento de Matemática y Física Aplicadas, Universidad Católica de la Santísima Concepción, Concepción, Chile
Adibekyan, V.; Instituto de Astrofísica e Ciências Do Espaço, Universidade Do Porto, CAUP, Porto, Portugal ; Departamento de Física e Astronomia, Faculdade de Ciências, Universidade Do Porto, Porto, Portugal
Bieryla, A.; Center for Astrophysics | Harvard and Smithsonian, Cambridge, United States
Bonfils, X.; Univ. Grenoble Alpes, CNRS, IPAG, Grenoble, France
Bouchy, F.; Observatoire de Genève, Université de Genève, Sauverny, Switzerland
Barclay, T.; NASA Goddard Space Flight Center, Greenbelt, United States ; University of Maryland, Baltimore County, Baltimore, United States
Brasseur, C.E.; Space Telescope Science Institute, Baltimore, United States
Borgniet, S.; LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Université de Paris, Meudon, France
Bourrier, V.; Observatoire de Genève, Université de Genève, Sauverny, Switzerland
Buchhave, L.; DTU Space, National Space Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
Behmard, A.; Division of Geological and Planetary Science, California Institute of Technology, Pasadena, United States
Beard, C.; Department of Physics and Astronomy, University of California Irvine, Irvine, United States
Batalha, N.M.; Department of Astronomy and Astrophysics, University of California, Santa Cruz, United States
Courcol, B.; Observatoire de Genève, Université de Genève, Sauverny, Switzerland
Cortés-Zuleta, P.; Aix Marseille Univ, CNRS, CNES, LAM, Marseille, France
Collins, K.; Center for Astrophysics | Harvard and Smithsonian, Cambridge, United States
Carmona, A.; Univ. Grenoble Alpes, CNRS, IPAG, Grenoble, France
Crossfield, I.J.M.; Department of Physics and Astronomy, University of Kansas, Lawrence, United States
Chontos, A.; Institute for Astronomy, University of Hawaiâ, Honolulu, United States
Delfosse, X.; Univ. Grenoble Alpes, CNRS, IPAG, Grenoble, France
Dalal, S.; Institut D’astrophysique de Paris, UMR 7095 CNRS, Université Pierre et Marie Curie, Paris, France
Deleuil, M.; Aix Marseille Univ, CNRS, CNES, LAM, Marseille, France
Demangeon, O.D.S.; Instituto de Astrofísica e Ciências Do Espaço, Universidade Do Porto, CAUP, Porto, Portugal ; Departamento de Física e Astronomia, Faculdade de Ciências, Universidade Do Porto, Porto, Portugal
Diáz, R.F.; International Center for Advanced Studies (ICAS) and ICIFI (CONICET), ECyT-UNSAM, Campus Miguelete, Buenos Aires, Argentina
Dumusque, X.; Observatoire de Genève, Université de Genève, Sauverny, Switzerland
Daylan, T.; Department of Physics, Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, United States
Dragomir, D.; Department of Physics and Astronomy, University of New Mexico, Albuquerque, United States
Delgado Mena, E.; Instituto de Astrofísica e Ciências Do Espaço, Universidade Do Porto, CAUP, Porto, Portugal
Dressing, C.; Department of Astronomy, University of California Berkeley, Berkeley, United States
Dai, F.; Division of Geological and Planetary Sciences, Pasadena, United States
Dalba, P.A.; Department of Earth and Planetary Sciences, University of California, Riverside, United States
Ehrenreich, D.; Observatoire de Genève, Université de Genève, Sauverny, Switzerland
Forveille, T.; Univ. Grenoble Alpes, CNRS, IPAG, Grenoble, France
Fulton, B.; NASA Exoplanet Science Institute/Caltech-IPAC, Pasadena, United States
Fetherolf, T.; Department of Earth and Planetary Sciences, University of California, Riverside, United States
Gaisné, G.; Univ. Grenoble Alpes, CNRS, IPAG, Grenoble, France
Giacalone, S.; Department of Astronomy, University of California Berkeley, Berkeley, United States
Riazi, N.; Department of Physics, Shahid Beheshti University, Tehran, Iran
Hoyer, S.; Aix Marseille Univ, CNRS, CNES, LAM, Marseille, France
Hobson, M.J.; Millennium Institute for Astrophysics, Chile ; Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile, Chile
Howard, A.W.; Department of Astronomy, California Institute of Technology, Pasadena, United States
Huber, D.; Institute for Astronomy, University of Hawaiâ, Honolulu, United States
Hill, M.L.; Department of Earth and Planetary Sciences, University of California, Riverside, United States
Hirsch, L.A.; Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, Stanford, United States
Isaacson, H.; Department of Astronomy, University of California Berkeley, Berkeley, United States ; Centre for Astrophysics, University of Southern Queensland, Toowoomba, Australia
Jenkins, J.; NASA Ames Research Center, United States
Kane, S.R.; Department of Earth and Planetary Sciences, University of California, Riverside, United States
Kiefer, F.; Institut D’astrophysique de Paris, UMR 7095 CNRS, Université Pierre et Marie Curie, Paris, France ; LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Université de Paris, Meudon, France
Luque, R.; Instituto de Astrofísica de Canarias, La Laguna, Spain ; Departamento de Astrofísica, Universidad de la Laguna, La Laguna, Spain
Latham, D.W.; Center for Astrophysics | Harvard and Smithsonian, Cambridge, United States
Lubin, J.; Department of Physics and Astronomy, University of California Irvine, Irvine, United States
Lopez, T.; Aix Marseille Univ, CNRS, CNES, LAM, Marseille, France
Mousis, O.; Aix Marseille Univ, CNRS, CNES, LAM, Marseille, France
Moutou, C.; Univ. de Toulouse, CNRS, IRAP, Toulouse, France
Montagnier, G.; Observatoire de Haute-Provence, CNRS, Université D’Aix-Marseille, France
Mignon, L.; Univ. Grenoble Alpes, CNRS, IPAG, Grenoble, France
Mayo, A.; Department of Astronomy, University of California Berkeley, Berkeley, United States
Močnik, T.; Gemini Observatory/NSFS NOIRLab, Hilo, United States
Murphy, J.M.A.; Department of Astronomy and Astrophysics, University of California, Santa Cruz, United States
Palle, E.; Instituto de Astrofísica de Canarias, La Laguna, Spain ; Departamento de Astrofísica, Universidad de la Laguna, La Laguna, Spain
Pepe, F.; Observatoire de Genève, Université de Genève, Sauverny, Switzerland
Petigura, E.A.; Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, United States
Rey, J.; Las Campanas Observatory, Carnegie Institution of Washington, La Serena, Chile
Ricker, G.; Department of Physics, Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, United States
Robertson, P.; Department of Physics and Astronomy, University of California Irvine, Irvine, United States
Roy, A.; Space Telescope Science Institute, Baltimore, United States ; Department of Physics and Astronomy, Johns Hopkins University, Baltimore, United States
Rubenzahl, R.A.; Department of Astronomy, California Institute of Technology, Pasadena, United States
Rosenthal, L.J.; Department of Astronomy, California Institute of Technology, Pasadena, United States
Santerne, A.; Aix Marseille Univ, CNRS, CNES, LAM, Marseille, France
Santos, N.C.; Instituto de Astrofísica e Ciências Do Espaço, Universidade Do Porto, CAUP, Porto, Portugal ; Departamento de Física e Astronomia, Faculdade de Ciências, Universidade Do Porto, Porto, Portugal
Sousa, S.G.; Instituto de Astrofísica e Ciências Do Espaço, Universidade Do Porto, CAUP, Porto, Portugal
Stassun, K.G.; Vanderbilt University, Department of Physics and Astronomy, Nashville, United States
Stalport, Manu ; Université de Liège - ULiège > Unités de recherche interfacultaires > Space sciences, Technologies and Astrophysics Research (STAR) ; Observatoire de Genève, Université de Genève, Sauverny, Switzerland
Scarsdale, N.; Department of Astronomy and Astrophysics, University of California, Santa Cruz, United States
Strøm, P.A.; Institut D’astrophysique de Paris, UMR 7095 CNRS, Université Pierre et Marie Curie, Paris, France ; Department of Physics, University of Warwick, Coventry, United Kingdom ; Centre for Exoplanets and Habitability, University of Warwick, Coventry, United Kingdom
Seager, S.; Department of Physics, Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, United States ; Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, United States ; Department of Aeronautics and Astronautics, MIT, Cambridge, United States
Segransan, D.; Observatoire de Genève, Université de Genève, Sauverny, Switzerland
Tenenbaum, P.; SETI Institute, NASA Ames Research Center, United States
Tronsgaard, R.; DTU Space, National Space Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
Udry, S.; Observatoire de Genève, Université de Genève, Sauverny, Switzerland
Vanderspek, R.; Department of Physics, Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, United States
Vakili, F.; Laboratoire J.-L. Lagrange, Observatoire de la Côte DAzur (OCA), Universite de Nice-Sophia Antipolis (UNS), CNRS, Nice Cedex 2, France
Winn, J.; Department of Astrophysical Sciences, Princeton University, Princeton, United States
Weiss, L.M.; Institute for Astronomy, University of Hawaiâ, Honolulu, United States
