planets and satellites: detection; planets and satellites: individual: Proxima c; stars: individual: Proxima; planets and satellites: terrestrial planets; instrumentation: high angular resolution; techniques: image processing; Astrophysics - Earth and Planetary Astrophysics; Astrophysics - Instrumentation and Methods for Astrophysics; Astrophysics - Solar and Stellar Astrophysics
Abstract :
[en] Context. Proxima Centauri is the closest star to the Sun and it is known to host an Earth-like planet in its habitable zone; very recently a second candidate planet was proposed based on radial velocities. At quadrature, the expected projected separation of this new candidate is larger than 1 arcsec, making it a potentially interesting target for direct imaging. <BR /> Aims: While identification of the optical counterpart of this planet is expected to be very difficult, successful identification would allow for a detailed characterization of the closest planetary system. <BR /> Methods: We searched for a counterpart in SPHERE images acquired over four years through the SHINE survey. In order to account for the expected large orbital motion of the planet, we used a method that assumes the circular orbit obtained from radial velocities and exploits the sequence of observations acquired close to quadrature in the orbit. We checked this with a more general approach that considers Keplerian motion, called K-stacker. <BR /> Results: We did not obtain a clear detection. The best candidate has signal-to-noise ratio (S/N) = 6.1 in the combined image. A statistical test suggests that the probability that this detection is due to random fluctuation of noise is <1%, but this result depends on the assumption that the distribution of noise is uniform over the image, a fact that is likely not true. The position of this candidate and the orientation of its orbital plane fit well with observations in the ALMA 12 m array image. However, the astrometric signal expected from the orbit of the candidate we detected is 3σ away from the astrometric motion of Proxima as measured from early Gaia data. This, together with the unexpectedly high flux associated with our direct imaging detection, means we cannot confirm that our candidate is indeed Proxima c. <BR /> Conclusions: On the other hand, if confirmed, this would be the first observation in imaging of a planet discovered from radial velocities and the second planet (after Fomalhaut b) of reflecting circumplanetary material. Further confirmation observations should be done as soon as possible. <P />The reduced images are only available at the CDS via anonymous ftp to <A href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A> (ftp://130.79.128.5) or via <A href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/638/A120">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/638/A120</A> <P />Based on data collected at the European Southern Observatory, Chile (ESO Programs 095.D-0309, 096.C-0241, 096.D-0252, 097.C-0865, 198.C-D0209, 099.D-0098, 099.C-0127.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Gratton, R.; INAF - Osservatorio Astronomico di Padova, Italy
Zurlo, A.; Núcleo de Astronomía, Facultad de Ingeniería y Ciencias, Universidad Diego Portales, Av. Ejercito 441, Santiago, Chile ; Escuela de Ingeniería Industrial, Facultad de Ingeniería y Ciencias, Universidad Diego Portales, Av. Ejercito 441, Santiago, Chile ; Aix-Marseille Université, CNRS, LAM (Laboratoire d'Astrophysique de Marseille) UMR 7326, 13388, Marseille, France
Le Coroller, H.; Aix-Marseille Université, CNRS, LAM (Laboratoire d'Astrophysique de Marseille) UMR 7326, 13388, Marseille, France
Damasso, M.; INAF - Osservatorio Astrofisico di Torino, Italy
Del Sordo, F.; Institute of Astrophysics, FORTH, GR-71110 Heraklion, Greece ; Department of Physics, University of Crete, 70013, Heraklion, Greece
Langlois, M.; CRAL, UMR 5574, CNRS, Université Lyon 1, ENS, 9 avenue Charles André, 69561, Saint Genis Laval Cedex, France ; Aix-Marseille Université, CNRS, LAM (Laboratoire d'Astrophysique de Marseille) UMR 7326, 13388, Marseille, France
Mesa, D.; INAF - Osservatorio Astronomico di Padova, Italy
Milli, J.; European Southern Observatory, Alonso de Cordova 3107, Casilla 19001 Vitacura, Santiago 19, Chile
Chauvin, G.; Univ. Grenoble Alpes, CNRS, IPAG, 38000, Grenoble, France ; Unidad Mixta Internacional Franco-Chilena de Astronomía, CNRS/INSU UMI 3386 and Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago, Chile
Desidera, S.; INAF - Osservatorio Astronomico di Padova, Italy
Hagelberg, J.; Observatoire de Genève, Université de Genève, 51 Chemin des Mailletes, 1290, Sauverny, Switzerland
Lagadec, E.; Université Côte d'Azur, OCA, CNRS, Lagrange, France
Vigan, A.; Aix-Marseille Université, CNRS, LAM (Laboratoire d'Astrophysique de Marseille) UMR 7326, 13388, Marseille, France
Boccaletti, A.; LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Univ. Paris Diderot, Sorbonne Paris Cité, 5 place Jules Janssen, 92195, Meudon, France
Bonnefoy, M.; Univ. Grenoble Alpes, CNRS, IPAG, 38000, Grenoble, France
Brandner, W.; Max Planck Institute for Astronomy, Königstuhl 17, 69117, Heidelberg, Germany
Brown, S.; Max Planck Institute for Astronomy, Königstuhl 17, 69117, Heidelberg, Germany
Cantalloube, F.; Max Planck Institute for Astronomy, Königstuhl 17, 69117, Heidelberg, Germany
Delorme, P.; Univ. Grenoble Alpes, CNRS, IPAG, 38000, Grenoble, France
D'Orazi, V.; INAF - Osservatorio Astronomico di Padova, Italy
Feldt, M.; Max Planck Institute for Astronomy, Königstuhl 17, 69117, Heidelberg, Germany
Galicher, R.; LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Univ. Paris Diderot, Sorbonne Paris Cité, 5 place Jules Janssen, 92195, Meudon, France
Henning, T.; Max Planck Institute for Astronomy, Königstuhl 17, 69117, Heidelberg, Germany
Janson, M.; Department of Astronomy, Stockholm University, Stockholm, Sweden
Kervella, P.; Université Côte d'Azur, OCA, CNRS, Lagrange, France
Lagrange, A.-M.; Univ. Grenoble Alpes, CNRS, IPAG, 38000, Grenoble, France
Lazzoni, C.; INAF - Osservatorio Astronomico di Padova, Italy
Ligi, R.; INAF - Osservatorio Astronomico di Brera, Milano, Italy
Maire, Anne-Lise ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > PSILab
Ménard, F.; Univ. Grenoble Alpes, CNRS, IPAG, 38000, Grenoble, France
Meyer, M.; Department of Astronomy, University of Michigan, 1085 S. Univer-sity Ave, Ann Arbor, MI, 48109-1107, USA
Mugnier, L.; ONERA (Office National d'Etudes et de Recherches Aérospatiales), BP72, 92322, Chatillon, France
Potier, A.; LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Univ. Paris Diderot, Sorbonne Paris Cité, 5 place Jules Janssen, 92195, Meudon, France
Rickman, E. L.; Observatoire de Genève, Université de Genève, 51 Chemin des Mailletes, 1290, Sauverny, Switzerland
Rodet, L.; Univ. Grenoble Alpes, CNRS, IPAG, 38000, Grenoble, France
Romero, C.; Univ. Grenoble Alpes, CNRS, IPAG, 38000, Grenoble, France
Schmidt, T.; LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Univ. Paris Diderot, Sorbonne Paris Cité, 5 place Jules Janssen, 92195, Meudon, France ; Hamburger Sternwarte, Gojenbergsweg 112, 21029, Hamburg, Germany
Sissa, E.; INAF - Osservatorio Astronomico di Padova, Italy
Sozzetti, A.; Institute of Astrophysics, FORTH, GR-71110 Heraklion, Greece
Szulágyi, J.; Center for Theoretical Astrophysics and Cosmology, Institute for Computational Science, University of Zürich, Zürich, Switzerland
Wahhaj, Z.; European Southern Observatory, Alonso de Cordova 3107, Casilla 19001 Vitacura, Santiago 19, Chile
Antichi, J.; INAF - Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, 50125, Firenze, Italy
Fusco, T.; ONERA (Office National d'Etudes et de Recherches Aérospatiales), BP72, 92322, Chatillon, France
Stadler, E.; Univ. Grenoble Alpes, CNRS, IPAG, 38000, Grenoble, France
Suarez, M.; European Southern Observatory, Karl-Schwarzschild-Strasse 2, 85748, Garching, Germany
Wildi, F.; Observatoire de Genève, Université de Genève, 51 Chemin des Mailletes, 1290, Sauverny, Switzerland)
Allard, F., Homeier, D., & Freytag, B. 2011, ASP Conf. Ser., 448, 91
Amara, A., & Quanz, S. P. 2012, MNRAS, 427, 948
Anglada-Escudé, G., Amado, P. J., Barnes, J., et al. 2016, Nature, 536, 437
Anglada, G., Amado, P. J., Ortiz, J. L., et al. 2017, ApJ, 850, L6
Arnold, L., & Schneider, J. 2004, A&A, 420, 1153
Bazot, M., Christensen-Dalsgaard, J., Gizon, L., & Benomar, O. 2016, MNRAS, 460, 1254
Benedict, G. F., & McArthur, B. E. 2020, Res. Notes Am. Astron. Soc., 4, 46
Benedict, G. F., McArthur, B., Chappell, D. W., et al. 1999, AJ, 118, 1086
Beuzit, J. L., Vigan, A., Mouillet, D., et al. 2019, A&A, 631, A155
Brandt, T. D. 2018, ApJS, 239, 31
Brandt, T. D. 2019, ApJS, 241, 39
Canup, R. M. 2010, Nature, 468, 943
Charnoz, S., Crida, A., Castillo-Rogez, J. C., et al. 2011, Icarus, 216, 535
Charnoz, S., Canup, R. M., Crida, A., & Dones, L. 2018, in Planetary Ring Systems, Properties, Structure, and Evolution, eds. M. S. Tiscareno, & C. D. Murray (Cambridge: Cambridge University Press), 517
Claudi, R. U., Turatto, M., Gratton, R. G., et al. 2008, SPIE Conf. Ser., 7014, 70143E
Currie, T., Debes, J., Rodigas, T. J., et al. 2012, ApJ, 760, L32
Damasso, M., & Del Sordo, F. 2017, A&A, 599, A126
Damasso, M., Del Sordo, F., Anglada-Escudé, G., et al. 2020, Sci. Adv., 6, 7467
Delorme, P., Meunier, N., Albert, D., et al. 2017, in SF2A-2017: Proceedings of the Annual meeting of the French Society of Astronomy and Astrophysics
C. Reylé, P. Di Matteo, F. Herpin, E. Lagadec, A. Lançon, Z. Meliani, & F. Royer, Di Dohlen, K., Langlois, M., Saisse, M., et al. 2008, SPIE Conf. Ser., 7014, 70143L
Evans, D. W., Riello, M., De Angeli, F., et al. 2018, A&A, 616, A4
Feliz, D. L., Blank, D. L., Collins, K. A., et al. 2019, AJ, 157, 226
Fujimoto, S., Ouchi, M., Ono, Y., et al. 2016, ApJS, 222, 1
Gaia Collaboration (Brown, A. G. A., et al.). 2018, A&A, 616, A1
Galicher, R., Marois, C., Zuckerman, B., & Macintosh, B. 2013, ApJ, 769, 42
Garraffo, C., Drake, J. J., & Cohen, O. 2016, ApJ, 833, L4
Howard, W. S., Tilley, M. A., Corbett, H., et al. 2018, ApJ, 860, L30
Lawler, S. M., Greenstreet, S., & Gladman, B. 2015, ApJ, 802, L20
Le Coroller, H., Nowak, M., Arnold, L., et al. 2015, in Twenty Years of Giant Exoplanets, eds. I. Boisse, O. Demangeon, F. Bouchy, & L. Arnold (France: Observatoire de Haute-Provence), 59
Le Coroller, H., Nowak, M., Delorme, P., et al. 2020, ArXiv e-prints [arXiv:2004.12878]
Lovis, C., Snellen, I., Mouillet, D., et al. 2017, A&A, 599, A16
Lurie, J. C., Henry, T. J., Jao, W.-C., et al. 2014, AJ, 148, 91
MacGregor, M. A.,Weinberger, A. J.,Wilner, D. J., Kowalski, A. F., & Cranmer, S. R. 2018, ApJ, 855, L2
Mamajek, E. E. 2012, ApJ, 754, L20
Mann, A. W., Feiden, G. A., Gaidos, E., Boyajian, T., & von Braun, K. 2015, ApJ, 804, 64
Marois, C., Lafrenière, D., Doyon, R., Macintosh, B., & Nadeau, D. 2006, ApJ, 641, 556
Mawet, D., Milli, J., Wahhaj, Z., et al. 2014, ApJ, 792, 97
Mawet, D., Hirsch, L., Lee, E. J., et al. 2019, AJ, 157, 33
Mesa, D., Gratton, R., Zurlo, A., et al. 2015, A&A, 576, A121
Mesa, D., Zurlo, A., Milli, J., et al. 2017, MNRAS, 466, L118
Nowak, M., Le Coroller, H., Arnold, L., et al. 2018, A&A, 615, A144
Pavlov, A., Möller-Nilsson, O., Feldt, M., et al. 2008, SPIE Conf. Ser., 7019, 701939
Ribas, I., Gregg, M. D., Boyajian, T. S., & Bolmont, E. 2017, A&A, 603, A58
Showalter, M. R., de Pater, I., Lissauer, J. J., & French, R. S. 2019, Nature, 566, 350
Snellen, I., de Kok, R., Birkby, J. L., et al. 2015, A&A, 576, A59
Soummer, R., Pueyo, L., & Larkin, J. 2012, ApJ, 755, L28