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129 results on '"R. G. Gratton"'

1. A new white dwarf companion around the Δμ star GJ 3346

Author: K. Mužić, Beth Biller, Valentina D'Orazi, Alessandro Sozzetti, Dino Mesa, Silvano Desidera, C. Fontanive, Mariangela Bonavita, R. G. Gratton, and Alice Zurlo
Subjects: Physics, Brightness, Proper motion, 530 Physics, 010308 nuclear & particles physics, Infrared, 520 Astronomy, White dwarf, Astronomy and Astrophysics, Astrophysics, Star (graph theory), Effective temperature, 01 natural sciences, Space and Planetary Science, 0103 physical sciences, Selection method, 010303 astronomy & astrophysics, Main sequence
Abstract: We present the discovery of a white dwarf companion at ∼3.6 arcsec from GJ 3346, a nearby (π ∼ 42 mas) K star observed with SPHERE@VLT as part of an open time survey for faint companions to objects with significant proper motion discrepancies (Δμ) between Gaia DR1 and Tycho-2. Syrius-like systems like GJ 3346 AB, which include a main-sequence star and a white dwarf, can be difficult to detect because of the intrinsic faintness of the latter. They have, however, been found to be common contaminants for direct imaging (DI) searches. White dwarfs have in fact similar brightness to substellar companions in the infrared, while being much brighter in the visible bands like those used by Gaia. Combining our observations with Gaia DR2 and with several additional archival data sets, we were able to fully constrain the physical properties of GJ 3346 B, such as its effective temperature (11 × 103 ± 500 K) as well as the cooling age of the system (648 ± 58 Myr). This allowed us to better understand the system history and to partially explain the discrepancies previously noted in the age indicators for this object. Although further investigation is still needed, it seems that GJ 3346, which was previously classified as young, is in fact most likely to be older than 4 Gyr. Finally, given that the mass (0.58 ± 0.01 M⊙) and separation (85 au) of GJ 3346 B are compatible with the observed Δμ, this discovery represents a further confirmation of the potential of this kind of dynamical signatures as selection methods for DI surveys targeting faint, substellar companions.
Published: 2020

2. Detecting life outside our solar system with a large high-contrast-imaging mission

Author: Ignasi Ribas, Th. Henning, P. Baudoz, M. Kasper, Pieter J. de Visser, Simon Albrecht, A.-M. Lagrange, Kevin Heng, Enric Palle, Didier Queloz, Nathan J. Mayne, Isabella Pagano, B.-O. Demory, Michiel Min, Olivier Guyon, R. van Boekel, Manuel López-Puertas, Ignas Snellen, Matthew A. Kenworthy, Guillem Anglada-Escudé, Daphne Stam, Julien Milli, Nikku Madhusudhan, Timothy M. Lenton, Garreth Ruane, John Lee Grenfell, Willy Benz, Christopher C. Stark, Valentina D'Orazi, Silvano Desidera, Mamadou N'Diaye, David Mouillet, E. J. W. de Mooij, Mark Claire, Christoph U. Keller, R. G. Gratton, Franck Selsis, A. L. Maire, Elsa Huby, Giampaolo Piotto, Alessandro Sozzetti, Jean-Luc Beuzit, Michaël Gillon, Anthony Boccaletti, Jayne Birkby, Matteo Brogi, Yamila Miguel, Arthur Vigan, Frans Snik, Beth Biller, B. S. Gaudi, Giuseppina Micela, Christiane Helling, Isabelle Baraffe, Oliver Krause, J. de Boer, Laura Kreidberg, Heike Rauer, Jean-Michel Desert, Markus Janson, Riccardo Claudi, Victoria S. Meadows, Ralf Launhardt, L. Carone, Lars A. Buchhave, Sasha Hinkley, Bertrand Mennesson, Leiden Observatory [Leiden], Universiteit Leiden, Sterrewacht Leiden, Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire de Paris, Université Paris sciences et lettres (PSL), Physikalisches Institut [Bern], Universität Bern [Bern] (UNIBE), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Institute for Astronomy [Edinburgh] (IfA), University of Edinburgh, Universiteit Leiden [Leiden], École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Universität Bern [Bern], Institut de Planétologie et d'Astrophysique de Grenoble (IPAG ), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS), Observatoire de la Côte d'Azur (OCA), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Low Energy Astrophysics (API, FNWI), University of St Andrews. School of Earth & Environmental Sciences, University of St Andrews. St Andrews Centre for Exoplanet Science, University of St Andrews. St Andrews Isotope Geochemistry, University of St Andrews. School of Physics and Astronomy, European Commission, European Research Council, Science and Technology Facilities Council (UK), Agencia Estatal de Investigación (España), Ministerio de Ciencia, Innovación y Universidades (España), Generalitat de Catalunya, Agenzia Spaziale Italiana, Istituto Nazionale di Astrofisica, Netherlands Organization for Scientific Research, Knut and Alice Wallenberg Foundation, Snellen, IAG [0000-0003-1624-3667], and Apollo - University of Cambridge Repository
Subjects: Solar System, life, Computer science, 01 natural sciences, 010309 optics, White paper, Spitzer Space Telescope, Planet, 0103 physical sciences, Agency (sociology), QB Astronomy, 010303 astronomy & astrophysics, QC, QB, [PHYS]Physics [physics], 520 Astronomy, imaging, Astronomy and Astrophysics, High contrast imaging, 3rd-DAS, 620 Engineering, QC Physics, mission, Space and Planetary Science, 5101 Astronomical Sciences, [SDU]Sciences of the Universe [physics], Extraterrestrial life, Systems engineering, Circumstellar habitable zone, 51 Physical Sciences
Abstract: Snellen, I.A.G. et al., In this White Paper, which was submitted in response to the European Space Agency (ESA) Voyage 2050 Call, we recommend the ESA plays a proactive role in developing a global collaborative effort to construct a large high-contrast imaging space telescope, e.g. as currently under study by NASA. Such a mission will be needed to characterize a sizable sample of temperate Earth-like planets in the habitable zones of nearby Sun-like stars and to search for extraterrestrial biological activity. We provide an overview of relevant European expertise, and advocate ESA to start a technology development program towards detecting life outside the Solar System., I.S. acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program under grant agreement No 694513. A.L.M. acknowledges the financial support of the F.R.S.-FNRS through a postdoctoral researcher grant. MB acknowledges support from the UK Science and Technology Facilities Council (STFC) research grant ST/S000631/1. I.R. acknowledges support from the Spanish Ministry of Science and Innovation and the European Regional Development Fund through grant PGC2018-098153-B-C33, as well as the support of the Generalitat de Catalunya/CERCA programme. E.P. acknowledges support from the Spanish Ministry of Science through grant PGC2018-098153-B-C31. J.M.D. acknowledges funding from the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation programme (grant agreement no. 679633; Exo-Atmos) Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. We acknowledge financial support from the ASI-INAF agreement n.2018-16-HH.0 We acknowledge financial support from Spanish MCIU SEV-2017-0709 and PID2019-110689RB-I00 awards. We acknowledge financial support from the ASI-INAF agreement n.2018-16-HH.0 AV acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 757561). KH acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 771620). NJM acknowledges funding from the Leverhulme Trust, and a Science and Technology Facilities Council Consolidated Grant (ST/R000395/1). PdV acknowledges funding from the Netherlands Organisation for Scientific Research NWO (Veni Grant No. 639.041.750). IP acknowledges financial support from the ASI-INAF agreements 2019-29-HH.06-HH.0 and 2015-019-R.1-2018. FS acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement no. 678194; FALCONER). MJ acknowledges support from the Knut and Alice Wallenberg foundation (KAW). JLB acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program under grant agreement No 805445. T.H. acknowledges support from the European Research Council under the Horizon 2020 Framework Program via the ERC Advanced Grant Origins 83 24 28. JLG acknowledges ISSI Team 464 for useful discussion.
Published: 2021

3. Limits on the presence of planets in systems with debris discs: HD 92945 and HD 107146

Author: Arthur Vigan, Silvano Desidera, Mickael Bonnefoy, N. Engler, Zahed Wahhaj, E. L. Rickman, Matthias Samland, Markus Janson, Miriam Keppler, Janis Hagelberg, Quentin Kral, Mariangela Bonavita, Ralf Launhardt, R. G. Gratton, C. Lazzoni, L. Weber, A. Pavlov, Anne-Marie Lagrange, Michael Meyer, Elisabetta Rigliaco, M. Feldt, Sergio Messina, N. Pawellek, Alice Zurlo, L. Gluck, O. Moeller-Nilsson, Maud Langlois, V. De Caprio, C. Perrot, Dino Mesa, V. Squicciarini, Julien Milli, Valentina D'Orazi, T. Schmidt, Sebastian Marino, Anthony Boccaletti, C. Fontanive, Sebastián Pérez, Gael Chauvin, A. L. Maire, Th. Henning, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)
Subjects: Physics, Earth and Planetary Astrophysics (astro-ph.EP), 010308 nuclear & particles physics, 530 Physics, 520 Astronomy, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Planetary system, 01 natural sciences, Debris, Stars, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, Planet, [SDU]Sciences of the Universe [physics], 0103 physical sciences, Anomaly (physics), 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics - Earth and Planetary Astrophysics
Abstract: Recent observations of resolved cold debris disks at tens of au have revealed that gaps could be a common feature in these Kuiper belt analogues. Such gaps could be evidence for the presence of planets within the gaps or closer-in near the edges of the disk. We present SPHERE observations of HD 92945 and HD 107146, two systems with detected gaps. We constrained the mass of possible companions responsible for the gap to 1-2 M Jup for planets located inside the gap and to less than 5 M Jup for separations down to 20 au from the host star. These limits allow us to exclude some of the possible configurations of the planetary systems proposed to explain the shape of the disks around these two stars. In order to put tighter limits on the mass at very short separations from the star, where direct imaging data are less effective, we also combined our data with astrometric measurements from Hipparcos and Gaia and radial velocity measurements. We were able to limit the separation and the mass of the companion potentially responsible for the proper motion anomaly of HD 107146 to values of 2-7 au and 2-5 M Jup , respectively., Comment: 17 pages, 14 Figures, accepted for publication on MNRAS
Published: 2021

4. HD142527: Quantitative disk polarimetry with SPHERE

Author: Francois Menard, Christian Ginski, S. Hunziker, Th. Henning, H. M. Schmid, Henning Avenhaus, Gael Chauvin, David Mouillet, Kjetil Dohlen, Maud Langlois, R. G. Gratton, C. Tschudi, Julien Milli, R. G. van Holstein, Carsten Dominik, Arthur Vigan, N. Engler, Jean-Luc Beuzit, J. Ma, Anthony Boccaletti, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), and Low Energy Astrophysics (API, FNWI)
Subjects: Protoplanetary disks, Polarimetry, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Protoplanetary disk, 01 natural sciences, Light scattering, Photometry (optics), Scattering, Polarization, 0103 physical sciences, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Physics, [PHYS]Physics [physics], Earth and Planetary Astrophysics (astro-ph.EP), 010308 nuclear & particles physics, Linear polarization, Techniques: polarimetric, Astronomy and Astrophysics, individual: HD 142527, instrumentation: high angular resolution, techniques: polarimetric, protoplanetary disks, polarization, scattering [stars], Polarization (waves), Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Instrumentation: high angular resolution, Degree of polarization, Astrophysics::Earth and Planetary Astrophysics, Stars: individual: HD 142527, Astrophysics - Earth and Planetary Astrophysics
Abstract: We present high-precision photometry and polarimetry for the protoplanetary disk around HD142527, with a focus on determining the light scattering parameters of the dust. We re-reduced polarimetric differential imaging data of HD142527 in the VBB (735 nm) and H-band (1625 nm) from the ZIMPOL and IRDIS subinstruments of SPHERE/VLT. With polarimetry and photometry based on reference star differential imaging, we were able to measure the linearly polarized intensity and the total intensity of the light scattered by the circumstellar disk with high precision. We used simple Monte Carlo simulations of multiple light scattering by the disk surface to derive constraints for three scattering parameters of the dust: the maximum polarization of $P_{\rm max}$, the asymmetry parameter $g$, and the single-scattering albedo $\omega$. We measure a reflected total intensity of $51.4\pm1.5$ mJy and $206\pm12$ mJy and a polarized intensity of $11.3\pm0.3$ mJy and $55.1\pm3.3$ mJy in the VBB and H-band, respectively. We also find in the visual range a degree of polarization that varies between $28\%$ on the far side of the disk and $17\%$ on the near side. The disk shows a red color for the scattered light intensity and the polarized intensity, which are about twice as high in the near-infrared when compared to the visual. We determine with model calculations the scattering properties of the dust particles and find evidence for strong forward scattering ($g\approx 0.5-0.75$), relatively low single-scattering albedo ($\omega \approx 0.2-0.5$), and high maximum polarization ($P_{\rm max} \approx 0.5-0.75$) at the surface on the far side of the disk for both observed wavelengths. The optical parameters indicate the presence of large aggregate dust particles, which are necessary to explain the high maximum polarization, the strong forward-scattering nature of the dust, and the observed red disk color., Comment: 20 pages, 14 figures
Published: 2021
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5. The Gaia-ESO Survey: A new approach to chemically characterising young open clusters

Author: G. M. De Silva, Gražina Tautvaišienė, Angela Bragaglia, Anais Gonneau, G. Casali, A. Hourihane, Simone Zaggia, G. G. Sacco, Luca Sbordone, Amelia Bayo, Paula Jofre, Donatella Romano, C. Melo, Maria Lugaro, Sofia Randich, Silvano Desidera, Katia Biazzo, E. Franciosini, Valentina D'Orazi, Clare Worley, Laura Magrini, Lorenzo Spina, R. G. Gratton, Gerard Gilmore, F. M. Jiménez-Esteban, V. A. Sheminova, M. Van der Swaelmen, Rodolfo Smiljanic, Lorenzo Monaco, Marco Pignatari, L. Morbidelli, Antonio Frasca, Thomas Bensby, G. Carraro, M. Baratella, Gilmore, Gerard [0000-0003-4632-0213], and Apollo - University of Cambridge Repository
Subjects: stars: abundances, FOS: Physical sciences, chemistry.chemical_element, Context (language use), Astrophysics, 01 natural sciences, Spectral line, 0103 physical sciences, Lanthanum, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Physics, Photosphere, 010308 nuclear & particles physics, Barium, Astronomy and Astrophysics, stars: solar-type, Yttrium, open clusters and associations: general, Astrophysics - Astrophysics of Galaxies, Stars, Astrophysics - Solar and Stellar Astrophysics, chemistry, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), stars: fundamental parameters, Open cluster
Abstract: Young open clusters (t, 26 pages, 14 figures, accepted for publication in A&A
Published: 2021

6. The SPHERE infrared survey for exoplanets (SHINE). I. Sample definition and target characterization

Author: E. L. Rickman, Julien Charton, Stéphane Udry, A. Roux, S. Rochat, Alice Zurlo, O. Möller-Nilsson, Riccardo Claudi, D. Fantinel, A. Pavlov, E. Covino, Christian Soenke, M. Kasper, Valentina D'Orazi, Anne-Lise Maire, Joshua E. Schlieder, J. Pragt, Enrico Cascone, Markus Janson, Mariangela Bonavita, T. Kopytova, C. Petit, P. Martinez, Mickael Bonnefoy, A. Deboulbe, Joany Andreina Manjarres Ramos, Franz-Josef Hambsch, L. Weber, Francois Menard, Thibaut Moulin, A. Bazzon, Yves Magnard, Norbert Hubin, F. Rigal, Thiam-Guan Tan, Eric Stadler, J.-F. Sauvage, T. O. B. Schmidt, Emmanuel Hugot, L. Gluck, Th. Henning, S. Benatti, Michael Meyer, Raphaël Galicher, Anne-Marie Lagrange, M. Feldt, M. Carle, Carsten Dominik, G. Rousset, Matthias Samland, Tristan Buey, Janis Hagelberg, H. M. Schmid, Philippe Feautrier, D. Le Mignant, Arnaud Sevin, H. LeCoroller, Pierre Baudoz, J. Antichi, Arthur Vigan, Wolfgang Brandner, Massimo Turatto, Gael Chauvin, Alain Origne, R. Ligi, P. Gigan, Bernardo Salasnich, C. Lazzoni, V. De Caprio, M. Jaquet, D. Gisler, Pascal Puget, Philippe Delorme, D. Perret, T. Fusco, Dino Mesa, E. Sissa, Francois Wildi, Silvano Desidera, D. Maurel, F. Madec, Joseph C. Carson, J. M. Alcalá, E. Rigliaco, S. Messina, J. Baudrand, Anne Costille, R. G. Gratton, M. Millward, André Müller, Beth Biller, Enrico Giro, Andrea Baruffolo, Faustine Cantalloube, Jean-Luc Beuzit, Ronald Roelfsema, Marcel Carbillet, Eric Lagadec, Kjetil Dohlen, R. Asensio-Torres, Anthony Cheetham, P. Rabou, M. Llored, Maud Langlois, P. Blanchard, Anthony Boccaletti, C. Fontanive, Marcos Suarez, L. Abe, and Low Energy Astrophysics (API, FNWI)
Subjects: PRE-MAIN SEQUENCE [STARS], HIGH CONTRAST IMAGING, STATISTICAL CONSTRAINTS, PLANET DETECTION, FOS: Physical sciences, Sample (statistics), Context (language use), Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, ROTATION [STARS], ROTATION PERIOD, 01 natural sciences, 7. Clean energy, FUNDAMENTAL PARAMETERS [STARS], Planet, 0103 physical sciences, GENERAL [PLANETS AND SATELLITES], DETECTION LIMITS, Astrophysics::Solar and Stellar Astrophysics, KINEMATICS AND DYNAMICS [STARS], ACTIVITY [STARS], 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, Physics, Earth and Planetary Astrophysics (astro-ph.EP), 010308 nuclear & particles physics, Astronomy and Astrophysics, TARGET CHARACTERIZATION, Light curve, Exoplanet, Characterization (materials science), SPHERES, Stars, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, ORIGINAL SAMPLE, STATISTICAL SAMPLES, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, Rotation (mathematics), SURVEYS, STARS, EXTRASOLAR PLANETS, Astrophysics - Earth and Planetary Astrophysics
Abstract: Large surveys with new-generation high-contrast imaging instruments are needed to derive the frequency and properties of exoplanet populations with separations from ~5 to 300 au. A careful assessment of the stellar properties is crucial for a proper understanding of when, where, and how frequently planets form, and how they evolve. The sensitivity of detection limits to stellar age makes this a key parameter for direct imaging surveys. Aims. We describe the SpHere INfrared survey for Exoplanets (SHINE), the largest direct imaging planet-search campaign initiated at the VLT in 2015 in the context of the SPHERE Guaranteed Time Observations of the SPHERE consortium. In this first paper we present the selection and the properties of the complete sample of stars surveyed with SHINE, focusing on the targets observed during the first phase of the survey (from February 2015 to February 2017). This early sample composed of 150 stars is used to perform a preliminary statistical analysis of the SHINE data, deferred to two companion papers presenting the survey performance, main discoveries, and the preliminary statistical constraints set by SHINE. Methods. Based on a large database collecting the stellar properties of all young nearby stars in the solar vicinity (including kinematics, membership to moving groups, isochrones, lithium abundance, rotation, and activity), we selected the original sample of 800 stars that were ranked in order of priority according to their sensitivity for planet detection in direct imaging with SPHERE. The properties of the stars that are part of the early statistical sample wererevisited, including for instance measurements from the Gaia Data Release 2. Rotation periods were derived for the vast majority of the late-type objects exploiting TESS light curves and dedicated photometric observations. Results. The properties of individual targets and of the sample as a whole are presented. © ESO 2021. SPHERE is an instrument designed and built by a consortium consisting of IPAG (Grenoble, France), MPIA (Heidelberg, Germany), LAM (Marseille, France), LESIA (Paris, France), Laboratoire Lagrange (Nice, France), INAF – Osservatorio di Padova (Italy), Observatoire de Genève (Switzerland), ETH Zürich (Switzerland), NOVA (Netherlands), ONERA (France) and ASTRON (Netherlands) in collaboration with ESO. SPHERE was funded by ESO, with additional contributions from CNRS (France), MPIA (Germany), INAF (Italy), FINES (Switzerland) and NOVA (Netherlands). SPHERE also received funding from the European Commission Sixth and Seventh Framework Programmes as part of the Optical Infrared Coordination Network for Astronomy (OPTICON) under grant number RII3-Ct-2004-001566 for FP6 (2004–2008), grant number 226 604 for FP7 (2009–2012) and grant number 312430 for FP7 (2013–2016). This research has made use of the SIMBAD database and Vizier services, operated at CDS, Strasbourg, France and of the Washington Double Star Catalog maintained at the US Naval Observatory. This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. This paper includes data collected with the TESS mission, obtained from the MAST data archive at the Space Telescope Science Institute (STScI). Funding for the TESS mission is provided by the NASA Explorer Program. STScI is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5–26555. This paper has made use of data products available in ESO archive. Program ID: 60.A-9036(A); 072.C-0488(E) (PI Mayor), 074.C-0364(A) (PI Robichon), 074.C-0037(A) (PI Gunther), 075.C-0202(A) (PI Gunther), 075.C-0689(A) (PI Galland), 076.C-0010(A) (PI Gunther), 077.C-0012(A) (PI Gunther), 077.C-0295(D) (PI Galland), 078.D-0245(C) (PI Dall), 079.C-0046(A) (PI Gunther), 080.D-0151(A) (PI Hatzes), 080.C-0712(A) (PI Desort), 180.C-0886(A) (PI Bonfils), 082.C-0718(B) (PI Bonfils), 082.C-0427(A) (PI Doellinger), 082.C-0390(A) (PI Weise), 183.C-0437(A) (PI Bonfils), 083.C-0794(A) (PI Chauvin), 084.C-1039(A) (PI Chauvin), 184.C-0815(B) (PI Desort), 089.C-0732(A) (PI Lo Curto), 191.C-0873(D) (PI Bonfils), 192.C-0224(A) (PI Lagrange), 097.C-0864(B) (PI Lannier), 098.C-0739(A) (PI Lagrange), 099.C-0205(A) (PI Lagrange), 099.C-0458(A) (PI Lo Curto), 1101.C-0557(A) (PI Lagrange). We have used data from the WASP public archive in this research. The WASP consortium comprises of the University of Cambridge, Keele University, University of Leicester, The Open University, The Queen’s University Belfast, St. Andrews University and the Isaac Newton Group. Funding for WASP comes from the consortium universities and from the UK’s Science and Technology Facilities Council. Based on data retrieved from the SOPHIE archive at Observatoire de Haute-Provence (OHP), available at http://atlas.obs-hp.fr/sophie/. We thank the anonymous referee for useful comments. S.D., V.D., D.M. and R.G. acknowledge the support by INAF/Frontiera through the “Progetti Premiali” funding scheme of the Italian Ministry of Education, University, and Research, the PRIN-INAF 2019 “Planetary systems at young ages” (PLATEA) and the ASI-INAF agreement n.2018-16-HH.0. AV acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 757561). A.M.L. acknowledges funding from Agence Nationale de la Recherche (France) under contract number ANR-14-CE33-0018. J.C. was supported by SC Space Grant and Fulbright Colombia. M.B. acknowledges funding by the UK Science and Technology Facilities Council (STFC) grant no. ST/M001229.
Published: 2021

7. Characterizing brown dwarf companions with IRDIS long-slit spectroscopy: HD 1160 B and HD 19467 B

Author: Daniel Kitzmann, Valentina D'Orazi, Kevin Heng, Anne-Lise Maire, R. G. Gratton, Silvano Desidera, Mickael Bonnefoy, S. Peretti, Dino Mesa, Anthony Boccaletti, Baptiste Lavie, Arthur Vigan, Department of Biochemistry and Molecular Biology, Mayo Clinic, INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Department of Geriatric Medicine, Centre Hospitalier Lyon Sud [CHU - HCL] (CHLS), Hospices Civils de Lyon (HCL)-Hospices Civils de Lyon (HCL), Physikalisches Institut [Bern], Universität Bern [Bern], Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Universität Bern [Bern] (UNIBE), Université de Genève = University of Geneva (UNIGE), Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)
Subjects: 010504 meteorology & atmospheric sciences, 530 Physics, Brown dwarf, FOS: Physical sciences, Astrophysics, 01 natural sciences, Spectral line, 0103 physical sciences, Angular resolution, Spectroscopy, infrared: planetary systems, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), 0105 earth and related environmental sciences, Long-slit spectroscopy, instrumentation: spectrographs, Earth and Planetary Astrophysics (astro-ph.EP), Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 520 Astronomy, Astronomy and Astrophysics, Spectral bands, 500 Science, Surface gravity, methods: data analysis, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, techniques: imaging spectroscopy, Low Mass, Astrophysics - Earth and Planetary Astrophysics
Abstract: The determination of the fundamental properties (mass, separation, age, gravity and atmospheric properties) of brown dwarf companions allows us to infer crucial informations on their formation and evolution mechanisms. Spectroscopy of substellar companions is available to date only for a limited number of objects (and mostly at very low resolution, R, 14 pages, 14 Figures. Accepted for publication on MNRAS
Published: 2020

8. RefPlanets: Search for reflected light from extrasolar planets with SPHERE/ZIMPOL

Author: H. M. Schmid, Michael Meyer, Eric Lagadec, François Ménard, Thierry Fusco, A. Pavlov, R. G. van Holstein, Ralf Siebenmorgen, J.-B. Daban, Julien Milli, P. Delorme, M. Suarez, P. Martinez, Arthur Vigan, Sascha P. Quanz, Mark Downing, Judit Szulágyi, Christoph U. Keller, Stéphane Udry, Riccardo Claudi, M. Kasper, Anne Costille, Frans Snik, Christian Ginski, Silvano Desidera, Andreas Bazzon, C. Thalmann, Anne-Lise Maire, Pascal Puget, Marcel Carbillet, S. Hunziker, Alice Zurlo, J.-L. Beuzit, David Mouillet, Pierre Baudoz, N. Engler, Norbert Hubin, G. Chauvin, J.-F. Sauvage, Massimo Turatto, Kjetil Dohlen, Anthony Boccaletti, Francois Wildi, R. Roelfsema, M. Feldt, Andrea Baruffolo, L. Abe, Carsten Dominik, E. Sissa, E. L. Rickman, Bernardo Salasnich, Maud Langlois, R. G. Gratton, Henning Avenhaus, Julien Girard, Th. Henning, D. Gisler, J. Pragt, Institute for Particle Physics and Astrophysics [ETH Zürich] (IPA), Department of Physics [ETH Zürich] (D-PHYS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Universidad de Chile = University of Chile [Santiago] (UCHILE), INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), European Southern Observatory (ESO), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), FRAMATOME, Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, DOTA, ONERA, Université Paris Saclay [Châtillon], ONERA-Université Paris-Saclay, Leiden Observatory [Leiden], Universiteit Leiden, Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Bulgarian Academy of Sciences (BAS), NOVA Optical Infrared Instrumentation Group, Institute of Astronomy [ETH Zürich], Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève = University of Geneva (UNIGE), Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174) (FEMTO-ST), Université de Technologie de Belfort-Montbeliard (UTBM)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Université Nice Sophia Antipolis (... - 2019) (UNS), Low Energy Astrophysics (API, FNWI), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Universiteit Leiden [Leiden], École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Université de Genève (UNIGE), Université de Technologie de Belfort-Montbeliard (UTBM)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Université de Franche-Comté (UFC), and Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [PHYS.ASTR.IM]Physics [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], 010504 meteorology & atmospheric sciences, FOS: Physical sciences, Library science, Astrophysics, 01 natural sciences, 0103 physical sciences, Agency (sociology), European commission, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Earth and Planetary Astrophysics (astro-ph.EP), Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], European research, Astronomy and Astrophysics, Methods observational, Joint research, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Christian ministry, Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract: RefPlanets is a guaranteed time observation (GTO) programme that uses the Zurich IMaging POLarimeter (ZIMPOL) of SPHERE/VLT for a blind search for exoplanets in wavelengths from 600-900 nm. The goals of this study are the characterization of the unprecedented high polarimetic contrast and polarimetric precision capabilities of ZIMPOL for bright targets, the search for polarized reflected light around some of the closest bright stars to the Sun and potentially the direct detection of an evolved cold exoplanet for the first time. For our observations of Alpha Cen A and B, Sirius A, Altair, Eps Eri and Tau Ceti we used the polarimetric differential imaging (PDI) mode of ZIMPOL which removes the speckle noise down to the photon noise limit for angular separations >0.6". We describe some of the instrumental effects that dominate the noise for smaller separations and explain how to remove these additional noise effects in post-processing. We then combine PDI with angular differential imaging (ADI) as a final layer of post-processing to further improve the contrast limits of our data at these separations. For good observing conditions we achieve polarimetric contrast limits of 15.0-16.3 mag at the effective inner working angle of about 0.13", 16.3-18.3 mag at 0.5" and 18.8-20.4 mag at 1.5". The contrast limits closer in (0.6"), the limits mainly depend on the brightness of the star and the total integration time. We compare our results with contrast limits from other surveys and review the exoplanet detection limits obtained with different detection methods. For all our targets we achieve unprecedented contrast limits. Despite the high polarimetric contrasts we are not able to find any additional companions or extended polarized light sources in the data that has been taken so far., 23 pages, 17 figures, 2 table, Accepted for publication in A&A
Published: 2020

9. The GAPS Programme at TNG: XXI. A GIARPS case study of known young planetary candidates: confirmation of HD 285507 b and refutation of AD Leonis b

Author: Marcello Lodi, A. F. Lanza, Andrea Bignamini, M. Sozzi, Gaetano Scandariato, C. Riverol, Jesus Maldonado, Luca Malavolta, Giuseppe Leto, R. G. Gratton, Massimo Cecconi, Katia Biazzo, Carlo Baffa, Riccardo Claudi, G. Falcini, N. Buchschacher, Marco Pedani, Elisabetta Giani, Silvano Desidera, Concepción Iglesias González, H. Perez Ventura, Luigi Mancini, Daniela Fantinel, Antonio Maggio, Salvo Scuderi, Ennio Poretti, Ulf Seemann, Andrea Tozzi, Matthias Mallonn, José Guerra, A. Galli, Giuseppina Micela, E. Alei, Valerio Nascimbeni, Avet Harutyunyan, Matteo Pinamonti, G. Frustagli, Aldo S. Bonomo, Monica Rainer, Alfio Puglisi, Aldo F. M. Fiorenzano, Livia Origlia, Serena Benatti, Alessandro Sozzetti, Isabella Pagano, Andrea Baruffolo, Adriano Ghedina, Paolo Giacobbe, M. Gonzalez, Ernesto Oliva, Ilaria Carleo, Francesca Ghinassi, Rosario Cosentino, Elvira Covino, M. Esposito, N. Hernandez, Giampaolo Piotto, M. Hernandez Diaz, Luca Fini, J. San Juan, Seth Redfield, M. Iuzzolino, Nicoletta Sanna, L. Riverol, Laura Affer, Francesco Borsa, Emilio Molinari, Mario Damasso, E. González-Álvarez, V. Billotti, Carleo, I, Malavolta, L, Lanza, A, Damasso, M, Desidera, S, Borsa, F, Mallonn, M, Pinamonti, M, Gratton, R, Alei, E, Benatti, S, Mancini, L, Maldonado, J, Biazzo, K, Esposito, M, Frustagli, G, Gonzalez-Alvarez, E, Micela, G, Scandariato, G, Sozzetti, A, Affer, L, Bignamini, A, Bonomo, A, Claudi, R, Cosentino, R, Covino, E, Fiorenzano, A, Giacobbe, P, Harutyunyan, A, Leto, G, Maggio, A, Molinari, E, Nascimbeni, V, Pagano, I, Pedani, M, Piotto, G, Poretti, E, Rainer, M, Redfield, S, Baffa, C, Baruffolo, A, Buchschacher, N, Billotti, V, Cecconi, M, Falcini, G, Fantinel, D, Fini, L, Galli, A, Ghedina, A, Ghinassi, F, Giani, E, Gonzalez, C, Gonzalez, M, Guerra, J, Hernandez DIaz, M, Hernandez, N, Iuzzolino, M, Lodi, M, Oliva, E, Origlia, L, Perez Ventura, H, Puglisi, A, Riverol, C, Riverol, L, San Juan, J, Sanna, N, Scuderi, S, Seemann, U, Sozzi, M, Tozzi, A, Claudi, R. [0000-0001-7707-5105], Leto, G. [0000-0002-0040-5011], Piotto, G. [0000-0002-9937-6387], Bonomo, A. S. [0000-0002-6177-198X], Sozzetti, A. [0000-0002-7504-365X], Biazzo, K. [0000-0002-1892-2180], Ghedina, A. [0000-0003-4702-5152], Damasso, M. [0000-0001-9984-4278], Cosentino, R. [0000-0003-1784-1431], Agenzia Spaziale Italiana (ASI), 2014-025-R.1.2015, European Commission (EC), Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737, and Agenzia Spaziale Italiana (ASI)
Subjects: Planetary system, astro-ph.SR, 010504 meteorology & atmospheric sciences, instrumentation: spectrographs, planetary systems, techniques: spectroscopic, stars: activity, techniques: radial velocities, FOS: Physical sciences, Orbital eccentricity, Astrophysics, 01 natural sciences, spectroscopic [Techniques], Planet, spectrographs, 0103 physical sciences, Hot Jupiter, Astrophysics::Solar and Stellar Astrophysics, Circular orbit, spectrographs [Instrumentation], 10. No inequality, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), 0105 earth and related environmental sciences, Planetary migration, Physics, Orbital elements, Earth and Planetary Astrophysics (astro-ph.EP), radial velocities [Techniques], Techniques: radial velocitie, Settore FIS/05, Astronomy and Astrophysics, Instrumentation: spectrograph, Radial velocity, Planetary systems, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, astro-ph.EP, Astrophysics::Earth and Planetary Astrophysics, activity [Stars], Astrophysics - Earth and Planetary Astrophysics
Abstract: Context. The existence of hot Jupiters is still not well understood. Two main channels are thought to be responsible for their current location: a smooth planet migration through the protoplanetary disk or the circularization of an initial highly eccentric orbit by tidal dissipation leading to a strong decrease in the semimajor axis. Different formation scenarios result in different observable effects, such as orbital parameters (obliquity and eccentricity) or frequency of planets at different stellar ages. Aims. In the context of the GAPS Young Objects project, we are carrying out a radial velocity survey with the aim of searching and characterizing young hot-Jupiter planets. Our purpose is to put constraints on evolutionary models and establish statistical properties, such as the frequency of these planets from a homogeneous sample. Methods. Since young stars are in general magnetically very active, we performed multi-band (visible and near-infrared) spectroscopy with simultaneous GIANO-B + HARPS-N (GIARPS) observing mode at TNG. This helps in dealing with stellar activity and distinguishing the nature of radial velocity variations: stellar activity will introduce a wavelength-dependent radial velocity amplitude, whereas a Keplerian signal is achromatic. As a pilot study, we present here the cases of two known hot Jupiters orbiting young stars: HD 285507 b and AD Leo b. Results. Our analysis of simultaneous high-precision GIARPS spectroscopic data confirms the Keplerian nature of the variation in the HD 285507 radial velocities and refines the orbital parameters of the hot Jupiter, obtaining an eccentricity consistent with a circular orbit. Instead, our analysis does not confirm the signal previously attributed to a planet orbiting AD Leo. This demonstrates the power of the multi-band spectroscopic technique when observing active stars., With funding from the Spanish government through the "María de Maeztu Unit of Excellence" accreditation (MDM-2017-0737)
Published: 2020

10. The GAPS programme at TNG XXIII. HD164922 d: close-in super-Earth discovered with HARPS-N in a system with a long-period Saturn mass companion

Author: Jesus Maldonado, L. Malavolta, Monica Rainer, Francesco Borsa, G. Bruno, A. F. Martinez Fiorenzano, Valerio Nascimbeni, Marcello Lodi, A. F. Lanza, Marco Molinaro, Gaetano Scandariato, Ilaria Carleo, Riccardo Claudi, Giuseppina Micela, Marco Pedani, Matteo Brogi, Andrea Bignamini, Avet Harutyunyan, Elvira Covino, Giuseppe Leto, M. Gonzalez, Katia Biazzo, R. G. Gratton, Luigi Mancini, Francesco Marzari, Rosario Cosentino, Laura Affer, Cristina Knapic, Mario Damasso, M. P. Di Mauro, G. Piotto, G. Frustagli, Domenico Nardiello, Silvano Desidera, Isabella Pagano, Serena Benatti, Alessandro Sozzetti, Ennio Poretti, D. Barbato, Aldo S. Bonomo, Antonio Maggio, Paolo Giacobbe, Matteo Pinamonti, Emilio Molinari, Benatti, S, Damasso, M, Desidera, S, Marzari, F, Biazzo, K, Claudi, R, Di Mauro, M, Lanza, A, Pinamonti, M, Barbato, D, Malavolta, L, Poretti, E, Sozzetti, A, Affer, L, Bignamini, A, Bonomo, A, Borsa, F, Brogi, M, Bruno, G, Carleo, I, Cosentino, R, Covino, E, Frustagli, G, Giacobbe, P, Gonzalez, M, Gratton, R, Harutyunyan, A, Knapic, C, Leto, G, Lodi, M, Maggio, A, Maldonado, J, Mancini, L, Martinez Fiorenzano, A, Micela, G, Molinari, E, Molinaro, M, Nardiello, D, Nascimbeni, V, Pagano, I, Pedani, M, Piotto, G, Rainer, M, Scandariato, G, Laboratoire d'Astrophysique de Marseille (LAM), and Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Rotation period, Solar System, Planetary system, planets and satellites: detection, astro-ph.SR, Gas giant, FOS: Physical sciences, Astrophysics, 01 natural sciences, Planetary systems, Planets and satellites: detection, Stars: individual: HD 164922, Techniques: radial velocities, Planet, 0103 physical sciences, techniques: radial velocities, stars: individual: HD 164922, 010303 astronomy & astrophysics, planetary systems, Solar and Stellar Astrophysics (astro-ph.SR), Earth and Planetary Astrophysics (astro-ph.EP), Physics, Super-Earth, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Techniques: radial velocitie, Settore FIS/05, Astronomy and Astrophysics, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, [SDU]Sciences of the Universe [physics], astro-ph.EP, Terrestrial planet, Astrophysics::Earth and Planetary Astrophysics, Circumstellar habitable zone, Astrophysics - Earth and Planetary Astrophysics
Abstract: In the framework of the Global Architecture of Planetary Systems (GAPS) project we collected more than 300 spectra with HARPS-N at the TNG for the bright G9V star HD164922. This target is known to host one gas giant planet in a wide orbit (Pb~1200 days, semi-major axis ~2 au) and a Neptune-mass planet with a period Pc ~76 days. We searched for additional low-mass companions in the inner region of the system. We compared the radial velocities (RV) and the activity indices derived from the HARPS-N time series to measure the rotation period of the star and used a Gaussian process regression to describe the behaviour of the stellar activity. We exploited this information in a combined model of planetary and stellar activity signals in an RV time-series composed of almost 700 high-precision RVs, both from HARPS-N and literature data. We performed a dynamical analysis to evaluate the stability of the system and the allowed regions for additional potential companions. Thanks to the high sensitivity of the HARPS-N dataset, we detect an additional inner super-Earth with an RV semi-amplitude of 1.3+/-0.2 m/s, a minimum mass of ~4+/-1 M_E and a period of 12.458+/-0.003 days. We disentangle the planetary signal from activity and measure a stellar rotation period of ~42 days. The dynamical analysis shows the long term stability of the orbits of the three-planet system and allows us to identify the permitted regions for additional planets in the semi-major axis ranges 0.18-0.21 au and 0.6-1.4 au. The latter partially includes the habitable zone of the system. We did not detect any planet in these regions, down to minimum detectable masses of 5 and 18 M_E, respectively. A larger region of allowed planets is expected beyond the orbit of planet b, where our sampling rules-out bodies with minimum mass > 50 M_E., 23 pages, 16 Figures. Accepted for publication on A&A
Published: 2020

11. The circumstellar environment of EX Lupi: SPHERE and SINFONI views

Author: Antonio Garufi, Dino Mesa, A. Kospal, R. G. van Holstein, Andrea Baruffolo, P. Blanchard, A. Zurlo, L. Weber, Péter Ábrahám, Th. Henning, Christian Ginski, Carsten Dominik, R. G. Gratton, D. Maurel, E. Rigliaco, Valentina D'Orazi, Silvano Desidera, Francois Menard, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), and Low Energy Astrophysics (API, FNWI)
Subjects: Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Context (language use), Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, stars: pre-main sequence, 01 natural sciences, circumstellar matter, Spectral line, stars: individual: EX Lup, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Emission spectrum, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, Line (formation), Earth and Planetary Astrophysics (astro-ph.EP), Physics, stars: formation, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, protoplanetary disks, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Accretion (astrophysics), T Tauri star, Stars, techniques: polarimetric, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Astrophysics of Galaxies (astro-ph.GA), Outflow, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract: EX Lup is a well-studied T Tauri star that represents the prototype of young eruptive stars EXors. In this paper we analyze new adaptive optics imaging and spectroscopic observations of EX Lup and its circumstellar environment in near-infrared in its quiescent phase. We observed EX Lup with the high contrast imager SPHERE/IRDIS in the dual-beam polarimetric imaging mode to resolve the circumstellar environment in near-infrared scattered light. We complemented these data with earlier SINFONI spectroscopy. We resolve for the first time in scattered light a compact feature around EX Lup azimuthally extending from 280deg to 360deg, and radially extending from 0.3arcsec to 0.55arcsec in the plane of the disk. We explore two different scenarios for the detected emission. One accounting for the emission as coming from the brightened walls of the cavity excavated by the outflow whose presence was suggested by ALMA observations in the J=3-2 line of 12CO. The other accounts for the emission as coming from an inclined disk. We detect for the first time a more extended circumstellar disk in scattered light, which shows that a region between 10 and 30 au is depleted of mum-size grains. We compare the J-, H- and K-band spectra obtained with SINFONI in quiescence with the spectra taken during the outburst, showing that all the emission lines were due to the episodic accretion event. Conclusions. Based on the morphology analysis we favour the scenario in which the scattered light is coming from a circumstellar disk rather than the outflow around EX Lup. We analyze the origin of the observed feature either as coming from a continuous circumstellar disk with a cavity, or from the illuminated wall of the outer disk or from a shadowed disk. Moreover, we discuss what is the origin of the mum-size grains depleted region, exploring the possibility that a sub-stellar companion may be the cause of it., Accepted for publication by A&A, 10 pages, 8 figures
Published: 2020

12. The search for disks or planetary objects around directly imaged companions: A candidate around DH Tau B

Author: E. L. Rickman, Markus Janson, Anthony Boccaletti, C. Fontanive, Matthias Samland, C. Lazzoni, S. Peretti, Francois Wildi, Mickael Bonnefoy, M. Houllé, T. Schmidt, C. Perrot, André Müller, Graeme Salter, Miriam Keppler, Raphaël Galicher, E. Sissa, Janis Hagelberg, Anne-Lise Maire, Th. Henning, Silvano Desidera, Arthur Vigan, Alice Zurlo, Steve Ertel, Beth Biller, Ken Rice, J. Lannier, Maud Langlois, R. Asensio-Torres, Wolfgang Brandner, Gael Chauvin, Faustine Cantalloube, R. G. Gratton, Esther Buenzli, Jean-Luc Beuzit, M. Cudel, Anthony Cheetham, David Mouillet, M. Kasper, Philippe Delorme, Dino Mesa, Anne-Marie Lagrange, J. L. Baudino, Mariangela Bonavita, Michael Meyer, M. Feldt, Eckhart Spalding, H. LeCoroller, Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)
Subjects: astro-ph.SR, 010504 meteorology & atmospheric sciences, 530 Physics, Library science, FOS: Physical sciences, Astrophysics, 01 natural sciences, 0103 physical sciences, Coordination network, Astrophysics::Solar and Stellar Astrophysics, European commission, 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), ComputingMilieux_MISCELLANEOUS, Solar and Stellar Astrophysics (astro-ph.SR), 0105 earth and related environmental sciences, Physics, [PHYS]Physics [physics], Earth and Planetary Astrophysics (astro-ph.EP), [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 520 Astronomy, European research, Astronomy and Astrophysics, 500 Science, Methods observational, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, astro-ph.EP, Christian ministry, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Earth and Planetary Astrophysics, astro-ph.IM
Abstract: In recent decades, thousands of substellar companions have been discovered with both indirect and direct methods of detection. In this paper, we focus our attention on substellar companions detected with the direct imaging technique, with the primary goal of investigating their close surroundings and looking for additional companions and satellites, as well as disks and rings. Any such discovery would shed light on many unresolved questions, particularly with regard to their possible formation mechanisms. To reveal bound features of directly imaged companions we need to suppress the contribution from the source itself. Therefore, we developed a method based on the negative fake companion (NEGFC) technique that first estimates the position in the field of view (FoV) and the flux of the imaged companion, then subtracts a rescaled model point spread function (PSF) from the imaged companion. Next it performs techniques, such as angular differential imaging (ADI), to further remove quasi-static patterns of the star. We applied the method to the sample of substellar objects observed with SPHERE during the SHINE GTO survey. Among the 27 planets and brown dwarfs we analyzed, we detected a possible point source close to DH Tau B. This candidate companion was detected in four different SPHERE observations, with an estimated mass of $\sim 1$ M\textsubscript{Jup}, and a mass ratio with respect to the brown dwarf of $1/10$. This binary system, if confirmed, would be the first of its kind, opening up interesting questions for the formation mechanism, evolution, and frequency of such pairs. In order to address the latter, the residuals and contrasts reached for 25 companions in the sample of substellar objects observed with SPHERE were derived. If the DH Tau Bb companion is real, the binary fraction obtained is $\sim 7\%$, which is in good agreement with the results obtained for field brown dwarfs., Comment: 19 pages, 17 figures
Published: 2020
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13. The GAPS Programme at TNG

Author: Aldo F. M. Fiorenzano, Andrea Bignamini, A. F. Lanza, Gaetano Scandariato, Luca Fossati, Valerio Nascimbeni, Cristina Knapic, Emilio Molinari, M. P. Di Mauro, M. Esposito, Antonio Maggio, Aldo S. Bonomo, Matteo Brogi, Walter Boschin, Monica Rainer, R. G. Gratton, Marco Pedani, Serena Benatti, Alessandro Sozzetti, Giuseppina Micela, Jesus Maldonado, Avet Harutyunyan, Giampaolo Piotto, Isabella Pagano, I. Raspantini, L. Pino, G. Frustagli, Elvira Covino, Daniela Sicilia, Francesco Borsa, Riccardo Claudi, Luigi Mancini, Rosario Cosentino, L. Di Fabrizio, Silvano Desidera, Ennio Poretti, ITA, GBR, DEU, ESP, and AUT
Subjects: planets and satellites: atmospheres, Physics, Nodal precession, Atmospheric escape, Settore FIS/05, stars: individual: WASP-33, Balmer series, Astronomy and Astrophysics, Context (language use), Astrophysics, Planetary system, Stars, symbols.namesake, Space and Planetary Science, Planet, techniques: radial velocities, symbols, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, planetary systems, techniques: spectroscopic, Stellar pulsation
Abstract: Context. Giant planets in short-period orbits around bright stars represent optimal candidates for atmospheric and dynamical studies of exoplanetary systems. Aims. We aim to analyse four transits of WASP-33b observed with the optical high-resolution HARPS-N spectrograph to confirm its nodal precession, study its atmosphere, and investigate the presence of star-planet interactions. Methods. We extracted the mean line profiles of the spectra using the least-squares deconvolution method, and we analysed the Doppler shadow and the radial velocities. We also derived the transmission spectrum of the planet, correcting it for the stellar contamination due to rotation, centre-to-limb variations, and pulsations. Results. We confirm the previously discovered nodal precession of WASP-33b, almost doubling the time coverage of the inclination and projected spin-orbit angle variation. We find that the projected obliquity reached a minimum in 2011, and we used this constraint to derive the geometry of the system, and in particular its obliquity at that epoch (ϵ = 113.99° ± 0.22°) and the inclination of the stellar spin axis (is = 90.11° ± 0.12°). We also derived the gravitational quadrupole moment of the star J2 = (6.73 ± 0.22) × 10−5, which we find to be in close agreement with the theoretically predicted value. Small systematics errors are computed by shifting the date of the minimum projected obliquity. We present detections of Hα and Hβ absorption in the atmosphere of the planet, with a contrast almost twice as small as that previously detected in the literature. We also find evidence for the presence of a pre-transit signal, which repeats in all four analysed transits and should thus be related to the planet. The most likely explanation lies in a possible excitation of a stellar pulsation mode by the presence of the planetary companion. Conclusions. A future common analysis of all available datasets in the literature will help shed light on the possibility that the observed Balmer lines’ transit depth variations are related to stellar activity and pulsation, and to set constraints on the planetary temperature–pressure structure and thus on the energetics possibly driving atmospheric escape. A complete orbital phase coverage of WASP-33b with high-resolution spectroscopic (and spectro-polarimetric) observations could help us to understand the nature of the pre-transit signal.
Published: 2021

14. Exploring the R CrA environment with SPHERE Discovery of a new stellar companion

Author: Maddalena Reggiani, T. Schmidt, Davide Fedele, R. G. Gratton, Markus Janson, Anne-Lise Maire, M. Kasper, Carlo F. Manara, F. Rigal, Giuseppe Lodato, R. Ligi, S. Antoniucci, Anthony Cheetham, Silvano Desidera, Myriam Benisty, Valentina D'Orazi, Gael Chauvin, Th. Henning, D. Gasparri, M. Barbieri, O. Möller-Nilsson, Riccardo Claudi, Arthur Vigan, Matthias Samland, Francois Wildi, M. G. Ubeira Gabellini, Maud Langlois, Dino Mesa, C. Petit, Anthony Boccaletti, C. Lazzoni, Michael Meyer, M. Feldt, M. E. van den Ancker, Alice Zurlo, Elisabetta Rigliaco, E. L. Rickman, Mickael Bonnefoy, G. van der Plas, Emmanuel Hugot, A. M. Lagrange, E. Sissa, INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), Instituto de Astronomia y ciencias Planetarias de Atacama (INCT), Universidad de Atacama, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Universidad Diego Portales [Santiago] (UDP), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Hamburger Sternwarte/Hamburg Observatory, Universität Hamburg (UHH), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Milano = University of Milan (UNIMI), INAF - Osservatorio Astronomico di Roma (OAR), Universidad de Chile = University of Chile [Santiago] (UCHILE), INAF - Osservatorio Astrofisico di Arcetri (OAA), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, European Southern Observatory (ESO), University of Michigan [Ann Arbor], University of Michigan System, Space Sciences, Technologies and Astrophysics Research Institute (STAR), Université de Liège, Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève = University of Geneva (UNIGE), AlbaNova University Center (ALBANOVA), Stockholm University, INAF - Osservatorio Astronomico di Brera (OAB), DOTA, ONERA, Université Paris Saclay (COmUE) [Châtillon], ONERA-Université Paris Saclay (COmUE), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), ANR-16-CE31-0013,PLANET-FORMING-DISKS,De meilleurs modèles pour de meilleures données(2016), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Università degli studi di Milano [Milano], Universidad de Chile, Université de Genève (UNIGE), DOTA, ONERA, Université Paris Saclay [Châtillon], ONERA-Université Paris-Saclay, Institut national des sciences de l'Univers (INSU - CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), and Università degli Studi di Milano [Milano] (UNIMI)
Subjects: Semi-major axis, ULTRAVIOLET, Astrophysics, 01 natural sciences, STARS: INDIVIDUAL: R CRA, Astrophysics::Solar and Stellar Astrophysics, pre-main sequence [stars], individual: R CrA [stars], 010303 astronomy & astrophysics, HERBIG AE/BE STARS, Physics, Nebula, SPECTROSCOPY, Astrophysics::Instrumentation and Methods for Astrophysics, imaging spectroscopy [techniques], VARIABILITY, Astrophysics - Solar and Stellar Astrophysics, Physical Sciences, Halo, Astrophysics::Earth and Planetary Astrophysics, OBJECTS, Type object, FOS: Physical sciences, METHODS: DATA ANALYSIS, Astrophysics::Cosmology and Extragalactic Astrophysics, LOW-MASS STARS, TECHNIQUES: IMAGING SPECTROSCOPY, Astronomy & Astrophysics, SEQUENCE, Photometry (optics), ASTROMETRY, 0103 physical sciences, data analysis [methods], PHOTOMETRY, Spectrograph, Solar and Stellar Astrophysics (astro-ph.SR), INSTRUMENTATION: SPECTROGRAPHS, Astrophysics::Galaxy Astrophysics, Very Large Telescope, Science & Technology, 010308 nuclear & particles physics, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], SINFONI, Astronomy and Astrophysics, 13. Climate action, Space and Planetary Science, STARS: PRE-MAIN SEQUENCE, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Data reduction, spectrographs [instrumentation]
Abstract: Aims. R Coronae Australis (R CrA) is the brightest star of the Coronet nebula of the Corona Australis (CrA) star forming region. It has very red colors, probably due to dust absorption and it is strongly variable. High contrast instruments allow for an unprecedented direct exploration of the immediate circumstellar environment of this star. Methods. We observed R CrA with the near-IR channels (IFS and IRDIS) of SPHERE at VLT. In this paper, we used four different epochs, three of them from open time observations while one is from the SPHERE guaranteed time. The data were reduced using the DRH pipeline and the SPHERE Data Center. On the reduced data we implemented custom IDL routines with the aim to subtract the speckle halo.We have also obtained pupil-tracking H-band (1.45-1.85 micron) observations with the VLT/SINFONI near-infrared medium-resolution (R~3000) spectrograph. Results. A companion was found at a separation of 0.156" from the star in the first epoch and increasing to 0.18400 in the final one. Furthermore, several extended structures were found around the star, the most noteworthy of which is a very bright jet-like structure North-East from the star. The astrometric measurements of the companion in the four epochs confirm that it is gravitationally bound to the star. The SPHERE photometry and the SINFONI spectrum, once corrected for extinction, point toward an early M spectral type object with a mass between 0.3 and 0.55 M?. The astrometric analyis provides constraints on the orbit paramenters: e~0.4, semi-major axis at 27-28 au, inclination of ~ 70{\deg} and a period larger than 30 years. We were also able to put constraints of few MJup on the mass of possible other companions down to separations of few tens of au., Comment: 11 pages, 13 figures, accepted by A&A
Published: 2019

15. A search for accreting young companions embedded in circumstellar disks: High-contrast Hα imaging with VLT/SPHERE

Author: Janis Hagelberg, Christophe Pinte, G. van der Plas, Emmanuel Hugot, Markus Janson, Anne-Marie Lagrange, G. Cugno, Alexander J. Bohn, F. Rigal, J. Pragt, Henning Avenhaus, Tomas Stolker, Philippe Feautrier, Pierre Baudoz, C. Mordasini, Yves Magnard, Arthur Vigan, Anne-Lise Maire, G. Chauvin, Anthony Cheetham, Carsten Dominik, A. Zurlo, H. M. Schmid, Michael Meyer, Julien Milli, M. Feldt, Julien Girard, M. Bonnefoy, R. G. Gratton, Silvano Desidera, Esther Buenzli, Ch. Ginski, R. Roelfsema, Francois Menard, Z. Wahhaj, S. Hunziker, Judit Szulágyi, Sascha P. Quanz, R. van Boekel, Maud Langlois, and Low Energy Astrophysics (API, FNWI)
Subjects: Physics, 010308 nuclear & particles physics, Astronomy and Astrophysics, Astrophysics, high angular resolution, Planets and satellites: detection, formation, Planet-disk interactions, Planetary systems [Techniques], 01 natural sciences, Circumstellar disk, Accretion (astrophysics), Photometry (optics), Stars, Space and Planetary Science, Planet, 0103 physical sciences, H-alpha, Continuum (set theory), Protoplanet, 010303 astronomy & astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract: Aims: We want to detect and quantify observables related to accretion processes occurring locally in circumstellar disks, which could be attributed to young forming planets. We focus on objects known to host protoplanet candidates and/or disk structures thought to be the result of interactions with planets. Methods: We analyzed observations of 6 young stars (age $3.5-10$ Myr) and their surrounding environments with the SPHERE/ZIMPOL instrument on the VLT in the H$\alpha$ filter (656 nm) and a nearby continuum filter (644.9 nm). Results: We re-detect the known accreting M-star companion HD142527 B with the highest published signal to noise to date in both H$\alpha$ and the continuum. We derive new astrometry ($r = 62.8^{+2.1}_{-2.7}$ mas and $\text{PA} = (98.7\,\pm1.8)^\circ$) and photometry ($\Delta$N_Ha=$6.3^{+0.2}_{-0.3}$ mag, $\Delta$B_Ha=$6.7\pm0.2$ mag and $\Delta$Cnt_Ha=$7.3^{+0.3}_{-0.2}$ mag) for the companion in agreement with previous studies, and estimate its mass accretion rate ($\dot{M}\approx1-2\,\times10^{-10}\,M_\odot\text{ yr}^{-1}$). A faint point-like source around HD135344 B (SAO206462) is also investigated, but a second deeper observation is required to reveal its nature. No other companions are detected. In the framework of our assumptions we estimate detection limits at the locations of companion candidates around HD100546, HD169142 and MWC758 and calculate that processes involving H$\alpha$ fluxes larger than $\sim8\times10^{-14}-10^{-15}\,\text{erg/s/cm}^2$ ($\dot{M}>10^{-10}-10^{-12}\,M_\odot\text{ yr}^{-1}$) can be excluded. Furthermore, flux upper limits of $\sim10^{-14}-10^{-15}\,\text{erg/s/cm}^2$ ($\dot{M}, Comment: Accepted for publication in A&A (20 pages, 18 figures)
Published: 2019

16. Two cold belts in the debris disk around the G-type star NZ Lupi

Author: Anne-Marie Lagrange, J.-F. Sauvage, T. Bhowmik, Janis Hagelberg, P. Thébault, S. Peretti, Maud Langlois, Th. Henning, Raphaël Galicher, Michael Meyer, T. O. B. Schmidt, Arthur Vigan, P. Janin-Potiron, Mariangela Bonavita, Q. Kral, M. Feldt, E. L. Rickman, H. Avenhaus, Francois Menard, J. C. Augereau, Julien Milli, Yves Magnard, H. Beust, D. Perret, Silvano Desidera, Anthony Boccaletti, O. Moeller-Nilsson, C. Perrot, L. Rodet, G. Chauvin, Anne-Lise Maire, M. Cudel, N. Pawellek, Dino Mesa, R. G. Gratton, E. Sissa, M. Bonnefoy, Anthony Cheetham, D. Maurel, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), European Southern Observatory (ESO), Space Sciences, Technologies and Astrophysics Research Institute (STAR), Université de Liège, Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), SUPA School of Physics and Astronomy [Edinburgh], University of Edinburgh, Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève = University of Geneva (UNIGE), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institute of Astronomy [ETH Zürich], Department of Physics [ETH Zürich] (D-PHYS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), University of Michigan [Ann Arbor], University of Michigan System, Universidad Tecnica Federico Santa Maria [Valparaiso] (UTFSM), DOTA, ONERA, Université Paris Saclay (COmUE) [Palaiseau], ONERA-Université Paris Saclay (COmUE), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), Université de Genève (UNIGE), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich)-Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), DOTA, ONERA, Université Paris Saclay [Palaiseau], ONERA-Université Paris-Saclay, Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Pawellek, Nicole [0000-0002-9385-9820], and Apollo - University of Cambridge Repository
Subjects: Planetesimal, Astronomical unit, Perturbation (astronomy), FOS: Physical sciences, techniques: image processing, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, stars: individual: NZ Lup, 01 natural sciences, individual: NZ Lup, planet-disk interactions, techniques: high angular resolution, techniques: image processing [stars], Integral field spectrograph, Planet, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), Astrophysics::Galaxy Astrophysics, Physics, Earth and Planetary Astrophysics (astro-ph.EP), Debris disk, Line-of-sight, 010308 nuclear & particles physics, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Astronomy and Astrophysics, Planetary system, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Earth and Planetary Astrophysics
Abstract: Context. Planetary systems hold the imprint of the formation and of the evolution of planets especially at young ages, and in particular at the stage when the gas has dissipated leaving mostly secondary dust grains. The dynamical perturbation of planets in the dust distribution can be revealed with high-contrast imaging in a variety of structures. Aims. SPHERE, the high-contrast imaging device installed at the VLT, was designed to search for young giant planets in long period, but is also able to resolve fine details of planetary systems at the scale of astronomical units in the scattered-light regime. As a young and nearby star, NZ Lup was observed in the course of the SPHERE survey. A debris disk had been formerly identified with HST/NICMOS. Methods. We observed this system in the near-infrared with the camera in narrow and broad band filters and with the integral field spectrograph. High contrasts are achieved by the mean of pupil tracking combined with angular differential imaging algorithms. Results. The high angular resolution provided by SPHERE allows us to reveal a new feature in the disk which is interpreted as a superimposition of two belts of planetesimals located at stellocentric distances of ~85 and ~115 au, and with a mutual inclination of about 5°. Despite the very high inclination of the disk with respect to the line of sight, we conclude that the presence of a gap, that is, a void in the dust distribution between the belts, is likely. Conclusions. We discuss the implication of the existence of two belts and their relative inclination with respect to the presence of planets., Astronomy & Astrophysics, 625, ISSN:0004-6361, ISSN:1432-0746
Published: 2019

17. Hint of curvature in the orbital motion of the exoplanet 51 Eridani b using 3 years of VLT/SPHERE monitoring

Author: Riccardo Claudi, E. L. Rickman, T. Schmidt, Th. Henning, Michael Meyer, Henning Avenhaus, Wolfgang Brandner, M. Cudel, Mickael Bonnefoy, Janis Hagelberg, S. Daemgen, Mariangela Bonavita, A. Roux, C. Fontanive, A. Zurlo, Arthur Vigan, L. Rodet, Dino Mesa, L. Abe, Johan Olofsson, Hervé Beust, Gérard Rousset, Matthias Samland, Raphaël Galicher, L. Weber, Francois Menard, Faustine Cantalloube, Anthony Boccaletti, Daniel Rouan, Jean-Luc Beuzit, Markus Janson, Valentina D'Orazi, Zahed Wahhaj, Stéphane Udry, Sergio Messina, Silvano Desidera, Beth Biller, Anne-Marie Lagrange, Kjetil Dohlen, Anne-Lise Maire, Anthony Cheetham, R. G. Gratton, F. Rigal, C. Lazzoni, Joseph C. Carson, H. Le Coroller, D. Melnick, Gael Chauvin, C. Perrot, E. Sissa, Alain Origne, Maud Langlois, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), Institut für Geowissenschaften [Potsdam], Universität Potsdam, Royal Observatory Edinburgh (ROE), University of Edinburgh, European Southern Observatory (ESO), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Stockholm University, Department of Physical Geography and Ecosystem Science [Lund], Lund University [Lund], Université libre de Bruxelles (ULB), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Institute of Astronomy [ETH Zürich], Department of Physics [ETH Zürich] (D-PHYS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Institute for Astronomy [Edinburgh] (IfA), Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), NOVA Optical Infrared Instrumentation Group, Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Observatoire de Paris - Site de Paris (OP), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS), Université Libre de Bruxelles [Bruxelles] (ULB), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich)-Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), University of Potsdam = Universität Potsdam, College of Charleston, Observatoire de Paris, Université Paris sciences et lettres (PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Université de Genève = University of Geneva (UNIGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010504 meteorology & atmospheric sciences, planets and satellites: dynamical evolution and stability, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], FOS: Physical sciences, techniques: image processing, Astrophysics, 01 natural sciences, Planet, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, planetary systems, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Orbital elements, Physics, Earth and Planetary Astrophysics (astro-ph.EP), [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Giant planet, techniques: high angular resolution, Astronomy and Astrophysics, Planetary system, Orbital period, methods: data analysis, Exoplanet, stars: individual: 51 Eridani, Orbit, Space and Planetary Science, Orbital motion, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Earth and Planetary Astrophysics
Abstract: Context. The 51 Eridani system harbors a complex architecture with its primary star forming a hierarchical system with the binary GJ 3305AB at a projected separation of 2000 au, a giant planet orbiting the primary star at 13 au, and a low-mass debris disk around the primary star with possibly a cold component and a warm component inferred from the spectral energy distribution. Aims. We aim to better constrain the orbital parameters of the known giant planet. Methods. We monitored the system over three years from 2015 to 2018 with the VLT/SPHERE exoplanet imaging instrument. Results. We measure an orbital motion for the planet of ~130 mas with a slightly decreasing separation (~10 mas) and find a hint of curvature. This potential curvature is further supported at 3$\sigma$ significance when including literature GPI astrometry corrected for calibration systematics. Fits of the SPHERE and GPI data using three complementary approaches provide broadly similar results. The data suggest an orbital period of 32$^{+17}_{-9}$ yr (i.e. 12$^{+4}_{-2}$ au in semi-major axis), an inclination of 133$^{+14}_{-7}$ deg, an eccentricity of 0.45$^{+0.10}_{-0.15}$, and an argument of periastron passage of 87$^{+34}_{-30}$ deg [mod 180 deg]. The time at periastron passage and the longitude of node exhibit bimodal distributions because we do not detect yet if the planet is accelerating or decelerating along its orbit. Given the inclinations of the planet's orbit and of the stellar rotation axis (134-144 deg), we infer alignment or misalignment within 18 deg for the star-planet spin-orbit. Further astrometric monitoring in the next 3-4 years is required to confirm at a higher significance the curvature in the planet's motion, determine if the planet is accelerating or decelerating on its orbit, and further constrain its orbital parameters and the star-planet spin-orbit., Comment: Accepted for publication in A&A. 15 pages, 12 figures, 6 tables. Updated following language editing, added epoch labels in Fig. 2, and changed color of orbital predictions in Fig. 5
Published: 2019
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18. Determining mass limits around HD163296 through SPHERE direct imaging data

Author: L. Gluck, Dino Mesa, Antonio Garufi, Silvano Desidera, Anne-Lise Maire, P. Delorme, Th. Henning, Janis Hagelberg, Daniel Rouan, A. M. Lagrange, Faustine Cantalloube, Alice Zurlo, Anthony Boccaletti, R. Ligi, Anthony Cheetham, F. Madec, M. Barbieri, M. Bonnefoy, Arthur Vigan, E. Sissa, C. Lazzoni, François Ménard, G. van der Plas, T. Schmidt, G. Chauvin, Joany Andreina Manjarres Ramos, Thierry Fusco, Michael Meyer, M. Feldt, Myriam Benisty, R. G. Gratton, E. L. Rickman, Valentina D'Orazi, O. Flasseur, Maud Langlois, V. De Caprio, INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), DOTA, ONERA, Université Paris Saclay [Palaiseau], ONERA-Université Paris-Saclay, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université de Genève = University of Geneva (UNIGE), DOTA, ONERA, Université Paris Saclay (COmUE) [Palaiseau], ONERA-Université Paris Saclay (COmUE), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), ANR-16-CE31-0013,PLANET-FORMING-DISKS,De meilleurs modèles pour de meilleures données(2016), Laboratoire Hubert Curien [Saint Etienne] (LHC), Institut d'Optique Graduate School (IOGS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Instituto de Astronomia y ciencias Planetarias de Atacama (INCT), Universidad de Atacama, INAF - Osservatorio Astronomico di Capodimonte (OAC), Observatoire de Paris, Université Paris sciences et lettres (PSL), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)
Subjects: Be star, FOS: Physical sciences, Direct imaging, Field of view, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Star (graph theory), Rotation, Protoplanetary disk, 01 natural sciences, Planet, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010306 general physics, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Astrophysics::Galaxy Astrophysics, Physics, [PHYS]Physics [physics], Earth and Planetary Astrophysics (astro-ph.EP), [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Astronomy and Astrophysics, Wavelength, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Earth and Planetary Astrophysics
Abstract: HD163296 is a Herbig Ae/Be star known to host a protoplanetary disk with a ringed structure. To explain the disk features, previous works proposed the presence of planets embedded into the disk. We have observed HD163296 with the near-infrared (NIR) branch of SPHERE composed by IRDIS and IFS with the aim to put tight constraints on the presence of substellar companions around this star. Despite the low rotation of the field of view during our observation we were able to put upper mass limits of few M_Jup around this object. These limits do not allow to give any definitive conclusion about the planets proposed through the disk characteristics. On the other hand, our results seem to exclude the presence of the only candidate proposed until now using direct imaging in the NIR even if some caution has to be taken considered the different wavelength bands of the two observations., Comment: Accepted for publication on MNRAS, 11 pages, 7 figures
Published: 2019
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19. HADES RV program with HARPS-N at TNG. IX. A super-Earth around the M dwarf Gl686

Author: Aldo S. Bonomo, Ignasi Ribas, Marco Pedani, Laura Affer, Antonio Maggio, Manuel Perger, Silvano Desidera, J. I. González Hernández, Ennio Poretti, Riccardo Claudi, Rafael Rebolo, Giuseppe Leto, B. Toledo-Padrón, Rosario Cosentino, Mario Damasso, Alessandro Sozzetti, A. Garrido Rubio, Elvira Covino, Paolo Giacobbe, A. F. Lanza, Gaetano Scandariato, A. Suárez Mascareño, R. G. Gratton, Matteo Pinamonti, Jesus Maldonado, Giuseppina Micela, Emilio Molinari, Francesco Borsa, ITA, ESP, and CHE
Subjects: Physics, Orbital elements, Earth and Planetary Astrophysics (astro-ph.EP), education.field_of_study, Super-Earth, Red dwarf, 010308 nuclear & particles physics, Stellar rotation, Population, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Orbital period, 01 natural sciences, Exoplanet, Space and Planetary Science, Planet, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, education, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract: The HArps-n red Dwarf Exoplanet Survey is providing a major contribution to the widening of the current statistics of low-mass planets, through the in-depth analysis of precise radial velocity measurements in a narrow range of spectral sub-types. As part of that program, we obtained radial velocity measurements of Gl 686, an M1 dwarf at d = 8.2 pc. The analysis of data obtained within an intensive observing campaign demonstrates that the excess dispersion is due to a coherent signal, with a period of 15.53 d. Almost simultaneous photometric observations were carried out within the APACHE and EXORAP programs to characterize the stellar activity and to distinguish periodic variations related to activity from signals due to the presence of planetary companions, complemented also with ASAS photometric data. We took advantage of the available radial velocity measurements for this target from other observing campaigns. The analysis of the radial velocity composite time series from the HIRES, HARPS and HARPS-N spectrographs, consisting of 198 measurements taken over 20 years, enabled us to address the nature of periodic signals and also to characterize stellar physical parameters (mass, temperature, and rotation). We report the discovery of a super-Earth orbiting at a distance of 0.092 AU from the host star Gl 686. Gl 686 b has a minimum mass of 7.1 +/- 0.9 MEarth and an orbital period of 15.532 +/- 0.002 d. The analysis of the activity indexes, correlated noise through a Gaussian process framework and photometry, provides an estimate of the stellar rotation period at 37 d, and highlights the variability of the spot configuration during the long timespan covering 20 yrs. The observed periodicities around 2000 d likely point to the existence of an activity cycle., Comment: 21 pages, 17 figures, changed paper numbering from X to IX, added a co-author. arXiv admin note: text overlap with arXiv:1607.03632
Published: 2019
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20. Blobs, spiral arms, and a possible planet around HD 169142

Author: G. Chauvin, Th. Henning, A. Pavlov, Michael Meyer, M. Feldt, R. G. Gratton, Anthony Boccaletti, Anne-Marie Lagrange, J. DeBoer, Pierre Baudoz, D. Fantinel, Anthony Cheetham, A. Zurlo, Silvano Desidera, Dino Mesa, Arthur Vigan, Maud Langlois, M. Jaquet, Valentina D'Orazi, C. Lazzoni, L. Gluck, Francois Wildi, F. Madec, Markus Janson, R. Ligi, E. Sissa, M. Bonnefoy, INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), INAF - Osservatorio Astronomico di Brera (OAB), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Laboratoire Franco-Chilien d'Astronomie (LFCA), Centre National de la Recherche Scientifique (CNRS)-Universidad de Chile = University of Chile [Santiago] (UCHILE), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), University of Michigan [Ann Arbor], University of Michigan System, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Stockholm University, Universidad Diego Portales [Santiago] (UDP), Universiteit Leiden [Leiden], Universidad de Chile = University of Chile [Santiago] (UCHILE)-Pontificia Universidad Católica de Chile (UC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Universidad de Concepción - University of Concepcion [Chile], Université de Genève = University of Geneva (UNIGE), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Universiteit Leiden, Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Universidad de Chile (UCHILE), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), and PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)
Subjects: planets and satellites: detection, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Star (graph theory), 01 natural sciences, Jupiter, Planet, Primary (astronomy), 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, Earth and Planetary Astrophysics (astro-ph.EP), Photosphere, Spiral galaxy, 010308 nuclear & particles physics, protoplanetary disks, techniques: high angular resolution, Astronomy and Astrophysics, stars: individual: HD 169142, Orbit, 13. Climate action, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, Spiral (railway), [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Earth and Planetary Astrophysics
Abstract: Young planets are expected to cause perturbations in protostellar disks that may be used to infer their presence. Clear detection of still-forming planets embedded within gas-rich disks is rare. HD 169142 is a very young Herbig Ae-Be star surrounded by a pre-transitional disk, composed of at least three rings. While claims of sub-stellar objects around this star have been made previously, follow-up studies remain inconclusive. We used SPHERE at ESO VLT to obtain a sequence of high-contrast images of the immediate surroundings of this star over about three years. This enables a photometric and astrometric analysis of the structures in the disk. While we were unable to definitively confirm the previous claims of a massive sub-stellar object at 0.1-0.15 arcsec from the star, we found both spirals and blobs within the disk. The spiral pattern may be explained as due to the presence of a primary, a secondary, and a tertiary arm excited by a planet of a few Jupiter masses lying along the primary arm, likely in the cavities between the rings. The blobs orbit the star consistently with Keplerian motion, allowing a dynamical determination of the mass of the star. While most of these blobs are located within the rings, we found that one of them lies in the cavity between the rings, along the primary arm of the spiral design. This blob might be due to a planet that might also be responsible for the spiral pattern observed within the rings and for the cavity between the two rings. The planet itself is not detected at short wavelengths, where we only see a dust cloud illuminated by stellar light, but the planetary photosphere might be responsible for the emission observed in the K band. The mass of this putative planet may be constrained using photometric and dynamical arguments; it should be between 1 and 4 Jupiter masses. The brightest blobs are found at the 1:2 resonance with this putative planet, Comment: Accepted on Astronomy and Astrophysics
Published: 2019

21. The HADES RV Programme with HARPS-N@TNG VIII. Gl15A: A multiple wide planetary system sculpted by binary interaction

Author: Paolo Giacobbe, Alessandro Sozzetti, Luca Malavolta, Riccardo Claudi, Rafael Rebolo, Giuseppe Leto, Andrea Bignamini, E. González-Álvarez, Marco Pedani, A. F. Martinez Fiorenzano, Giampaolo Piotto, Emilio Molinari, Jesus Maldonado, A. Suárez Mascareño, Mario Damasso, Giuseppina Micela, Laura Affer, B. Toledo-Padrón, Rosario Cosentino, Matteo Pinamonti, Manuel Perger, Ignasi Ribas, Silvano Desidera, Isabella Pagano, J. I. González Hernández, Aldo S. Bonomo, A. F. Lanza, Gaetano Scandariato, R. G. Gratton, Francesco Marzari, and Francesco Borsa
Subjects: Physics, Earth and Planetary Astrophysics (astro-ph.EP), Super-Earth, 010504 meteorology & atmospheric sciences, media_common.quotation_subject, Binary number, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Planetary system, 01 natural sciences, Radial velocity, Orbit, Amplitude, 13. Climate action, Space and Planetary Science, Planet, 0103 physical sciences, Astrophysics::Earth and Planetary Astrophysics, Eccentricity (behavior), 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, media_common, Astrophysics - Earth and Planetary Astrophysics
Abstract: We present 20 years of radial velocity (RV) measurements of the M1 dwarf Gl15A, combining 5 years of intensive RV monitoring with the HARPS-N spectrograph with 15 years of archival HIRES/Keck RV data. We carry out an MCMC-based analysis of the RV time series, inclusive of Gaussian Process (GP) approach to the description of stellar activity induced RV variations. Our analysis confirms the Keplerian nature and refines the orbital solution for the 11.44-day period super Earth, Gl15A\,b, reducing its amplitude to $1.68^{+0.17}_{-0.18}$ m s$^{-1}$ ($M \sin i = 3.03^{+0.46}_{-0.44}$ M$_\oplus$), and successfully models a long-term trend in the combined RV dataset in terms of a Keplerian orbit with a period around 7600 days and an amplitude of $2.5^{+1.3}_{-1.0}$ m s$^{-1}$, corresponding to a super-Neptune mass ($M \sin i = 36^{+25}_{-18}$ M$_\oplus$) planetary companion. We also discuss the present orbital configuration of Gl15A planetary system in terms of the possible outcomes of Lidov-Kozai interactions with the wide-separation companion Gl15B in a suite of detailed numerical simulations. In order to improve the results of the dynamical analysis, we derive a new orbital solution for the binary system, combining our RV measurements with astrometric data from the WDS catalogue. The eccentric Lidov-Kozai analysis shows the strong influence of Gl15B on the Gl15A planetary system, which can produce orbits compatible with the observed configuration for initial inclinations of the planetary system between $75^\circ$ and $90^\circ$, and can also enhance the eccentricity of the outer planet well above the observed value, even resulting in orbital instability, for inclinations around $0^\circ$ and $15^\circ - 30^\circ$. The Gl15A system is the multi-planet system closest to Earth, at $3.57$ pc, and hosts the longest period RV sub-jovian mass planet discovered so far., 19 pages, 14 figures, accepted for publication in A\&A
Published: 2018

22. Investigating the young solar system analog HD 95086. A combined HARPS and SPHERE exploration

Author: Eric Lagadec, C. Perrot, H. Le Coroller, R. van Boekel, Silvano Desidera, N. Meunier, D. Perret, P. Feautrier, Mickael Bonnefoy, Mariangela Bonavita, Christian Ginski, C. Lazzoni, Miriam Keppler, Joany Andreina Manjarres Ramos, C. Fontanive, Matthias Samland, S. Peretti, Johan Olofsson, P. Janin-Potiron, J. Hagelberg, H. Beust, Wolfgang Brandner, Markus Janson, S. Rochat, J.-L. Beuzit, Attila Moór, S. Borgniet, Th. Henning, M. Cudel, A. Boccaletti, Anthony Cheetham, G. Salter, L. Rodet, Anne-Lise Maire, G. Chauvin, Sergio Messina, Andreas Bazzon, J. Lannier, Sascha P. Quanz, Anne-Marie Lagrange, R. G. Gratton, P. Delorme, Raphaël Galicher, Maud Langlois, Francois Menard, Arthur Vigan, J. de Boer, David Mouillet, Henning Avenhaus, E. Sissa, T. Bhowmik, Dino Mesa, J. Milli, Q. Kral, D. Le Mignant, T. O. B. Schmidt, Michael Meyer, M. Feldt, and Alice Zurlo
Subjects: Physics, Debris disk, Solar System, Giant planet, Astronomy and Astrophysics, Astrophysics, Planetary system, 01 natural sciences, 010309 optics, Radial velocity, Orbit, Space and Planetary Science, Planet, 0103 physical sciences, Spectral energy distribution, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics
Abstract: Context. HD 95086 (A8V, 17 Myr) hosts a rare planetary system for which a multi-belt debris disk and a giant planet of 4–5 MJup have been directly imaged. Aims. Our study aims to characterize the global architecture of this young system using the combination of radial velocity and direct imaging observations. We want to characterize the physical and orbital properties of HD 95086 b, search for additional planets at short and wide orbits and image the cold outer debris belt in scattered light. Methods. We used HARPS at the ESO 3.6 m telescope to monitor the radial velocity of HD 95086 over two years and investigate the existence of giant planets at less than 3 au orbital distance. With the IRDIS dual-band imager and the IFS integral field spectrograph of SPHERE at VLT, we imaged the faint circumstellar environment beyond 10 au at six epochs between 2015 and 2017. Results. We do not detect additional giant planets around HD 95086. We identify the nature (bound companion or background contaminant) of all point-like sources detected in the IRDIS field of view. None of them correspond to the ones recently discovered near the edge of the cold outer belt by ALMA. HD 95086 b is resolved for the first time in J-band with IFS. Its near-infrared spectral energy distribution is well fitted by a few dusty and/or young L7–L9 dwarf spectral templates. The extremely red 1–4 μm spectral distribution is typical of low-gravity objects at the L/T spectral type transition. The planet’s orbital motion is resolved between January 2015 and May 2017. Together with past NaCo measurements properly re-calibrated, our orbital fitting solutions favor a retrograde low to moderate-eccentricity orbit e = 0.2+0.3−0.2, with a semi-major axis ~52 au corresponding to orbital periods of ~288 yr and an inclination that peaks at i = 141°, which is compatible with a planet-disk coplanar configuration. Finally, we report the detection in polarimetric differential imaging of the cold outer debris belt between 100 and 300 au, consistent in radial extent with recent ALMA 1.3 mm resolved observations.
Published: 2018

23. GIARPS: commissioning and first scientific results

Author: Serena Benatti, Alessandro Sozzetti, Luca Fini, G. Falcini, Jesus Maldonado, J. San Juan Gómez, Livia Origlia, Andrea Baruffolo, M. Sozzi, Nicoletta Sanna, Daniela Fantinel, Massimo Cecconi, Carlo Baffa, M. Hernandez Diaz, Adriano Ghedina, C. Riverol, Luca Malavolta, José Guerra, Ulf Seemann, Ernesto Oliva, E. Gonzalez-Alvarez, Valdemaro Biliotti, L. Riverol, Monica Rainer, H. Perez Ventura, M. Gonzalez, Salvo Scuderi, A. Galli, C. Gonzalez, Giuseppina Micela, Rosario Cosentino, N. Buchschacher, Emilio Molinari, Riccardo Claudi, Elisabetta Giani, Marcello Lodi, R. G. Gratton, Francesca Ghinassi, Andrea Tozzi, Avet Harutyunyan, M. Iuzzolino, I. Carleo, N. Hernandez, and Alfio Puglisi
Subjects: Physics, Single exposure, Project commissioning, Astronomy, 01 natural sciences, Exoplanet, 010309 optics, symbols.namesake, Planet, 0103 physical sciences, Hot Jupiter, Galileo (satellite navigation), symbols, Terrestrial planet, 010303 astronomy & astrophysics, Spectrograph
Abstract: GIARPS (GIAno and haRPS) is a project devoted to have on the same focal station of the Telescopio Nazionale Galileo (TNG) both high resolution spectrographs, HARPS-N (VIS) and GIANO-B (NIR), working simultaneously. This could be considered the first and unique worldwide instrument providing cross-dispersed echelle spectroscopy at a resolution of 50,000 in the NIR range and 115,000 in the VIS and over in a wide spectral range (0.383-2.45 μm) in a single exposure. The science case is very broad, given the versatility of such an instrument and its large wavelength range. A number of outstanding science cases encompassing mainly extra-solar planet science starting from rocky planets search and hot Jupiters to atmosphere characterization can be considered. Furthermore both instruments can measure high precision radial velocities by means the simultaneous thorium technique (HARPS-N) and absorbing cell technique (GIANO-B) in a single exposure. Other science cases are also possible. GIARPS, as a brand new observing mode of the TNG started after the moving of GIANO-A (fiber fed spectrograph) from Nasmyth-A to Nasmyth-B where it was re-born as GIANO-B (no more fiber feed spectrograph). The official Commissioning finished on March 2017 and then it was offered to the community. Despite the work is not finished yet. In this paper we describe the preliminary scientific results obtained with GIANO-B and GIARPS observing mode with data taken during commissioning and first open time observations.
Published: 2018

24. New disk discovered with VLT/SPHERE around the M star GSC 07396-00759

Author: A. Delboulbé, P. Feautrier, P. Thébault, Gael Chauvin, Jean-Charles Augereau, Maud Langlois, C. Lazzoni, F. Rigal, S. Messina, François Ménard, Silvano Desidera, Anthony Boccaletti, Anne-Lise Maire, Mickael Bonnefoy, D. Maurel, T. Schmidt, Judit Szulágyi, Valentina D'Orazi, R. G. Gratton, E. Sissa, Joshua E. Schlieder, Elie Sezestre, T. Bhowmik, A. M. Lagrange, Elisabetta Rigliaco, Markus Janson, Joany Andreina Manjarres Ramos, E. Stadler, Janis Hagelberg, Quentin Kral, M. Feldt, Alice Zurlo, Arthur Vigan, Johan Olofsson, Dino Mesa, INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de l'intégration, du matériau au système (IMS), Université Sciences et Technologies - Bordeaux 1-Institut Polytechnique de Bordeaux-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astrofisico di Catania (OACT), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Réactivité de Surface (LRS), Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Department of Astronomy, Stockholm University, Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), ANR-16-CE31-0013,PLANET-FORMING-DISKS,De meilleurs modèles pour de meilleures données(2016), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES)
Subjects: Library science, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, 0103 physical sciences, Coordination network, media_common.cataloged_instance, Astrophysics::Solar and Stellar Astrophysics, European commission, European union, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Astrophysics::Galaxy Astrophysics, media_common, Physics, [PHYS]Physics [physics], Earth and Planetary Astrophysics (astro-ph.EP), 010308 nuclear & particles physics, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], protoplanetary disks, techniques: high angular resolution, Astronomy and Astrophysics, Space and Planetary Science, Christian ministry, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], stars: individual: GSC 07396–00759, Astrophysics - Earth and Planetary Astrophysics
Abstract: Debris disks are usually detected through the infrared excess over the photospheric level of their host star. The most favorable stars for disk detection are those with spectral types between A and K, while the statistics for debris disks detected around low-mass M-type stars is very low, either because they are rare or because they are more difficult to detect. Terrestrial planets, on the other hand, may be common around M-type stars. Here, we report on the discovery of an extended (likely) debris disk around the M-dwarf GSC 07396-00759. The star is a wide companion of the close accreting binary V4046 Sgr. The system probably is a member of the $\beta$ Pictoris Moving Group. We resolve the disk in scattered light, exploiting high-contrast, high-resolution imagery with the two near-infrared subsystems of the VLT/SPHERE instrument, operating in the YJ bands and the H2H3 doublet. The disk is clearly detected up to 1.5" ($\sim110$ au) from the star and appears as a ring, with an inclination $i\sim83$ degree, and a peak density position at $\sim 70$ au. The spatial extension of the disk suggests that the dust dynamics is affected by a strong stellar wind, showing similarities with the AU Mic system that has also been resolved with SPHERE. The images show faint asymmetric structures at the widest separation in the northwest side. We also set an upper limit for the presence of giant planets to $2 M_J$. Finally, we note that the 2 resolved disks around M-type stars of 30 such stars observed with SPHERE are viewed close to edge-on, suggesting that a significant population of debris disks around M dwarfs could remain undetected because of an unfavorable orientation., Comment: 10 pages, 10 figures, in press by A&A
Published: 2018
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25. First scattered light detection of a nearly edge-on transition disk around the T Tauri star RY Lupi

Author: A. Pohl, Alice Zurlo, Anne-Lise Maire, R. van Boekel, T. Kopytova, C. Petit, Mickael Bonnefoy, Marcos Suarez, Tristan Buey, Dino Mesa, Christian Ginski, Myriam Benisty, R. G. Gratton, R. Ligi, P. Blanchard, Anthony Cheetham, Enrico Cascone, Anthony Boccaletti, Yves Magnard, Th. Henning, Raphaël Galicher, Maud Langlois, Carsten Dominik, Hubert Klahr, L. Weber, J. de Boer, Arthur Vigan, Christophe Pinte, Quentin Kral, Francois Menard, M. Feldt, Anne-Marie Lagrange, S. Peretti, Markus Janson, S. Messina, Julien Girard, Henning Avenhaus, Gael Chauvin, L. Denneulin, O. Möller-Nilsson, J. Pragt, Silvano Desidera, Tomas Stolker, E. Sissa, Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Heidelberg University, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), Instituto de Astronomia y ciencias Planetarias de Atacama (INCT), Universidad de Atacama, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), Leiden Observatory [Leiden], Universiteit Leiden [Leiden], Stockholm University, University of Cambridge [UK] (CAM), Geneva Observatory, University of Geneva [Switzerland], European Southern Observatory (ESO), INAF - Osservatorio Astronomico di Capodimonte (OAC), DOTA, ONERA, Université Paris Saclay [Châtillon], ONERA-Université Paris-Saclay, NOVA Optical Infrared Instrumentation Group, Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), DOTA, ONERA, Université Paris Saclay (COmUE) [Châtillon], ONERA-Université Paris Saclay (COmUE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Genève = University of Geneva (UNIGE), Universiteit Leiden, Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), and Low Energy Astrophysics (API, FNWI)
Subjects: INFRARED DEVICES, NUMERICAL [METHODS], Polarimetry, FOS: Physical sciences, Context (language use), DUST, POLARIMETERS, Astrophysics, 01 natural sciences, methods: numerical, 010309 optics, Planet, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Angular resolution, observational, techniques: polarimetric [protoplanetary disks, planet-disk interactions, methods], SILICATES, Adaptive optics, NUMERICAL METHODS, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, Earth and Planetary Astrophysics (astro-ph.EP), PLANET-DISK INTERACTIONS, POLARIMETRIC [TECHNIQUES], ADAPTIVE OPTICS, Spiral galaxy, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], protoplanetary disks, NUMERICALS [METHODS], Astronomy and Astrophysics, Wavelength, T Tauri star, techniques: polarimetric, LIGHT, 13. Climate action, Space and Planetary Science, OBSERVATIONAL [METHODS], Astrophysics::Earth and Planetary Astrophysics, LIGHT SCATTERING, methods: observational, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], PROTOPLANETARY DISKS, STARS, Astrophysics - Earth and Planetary Astrophysics, PLANETS
Abstract: Context. Transition disks are considered sites of ongoing planet formation, and their dust and gas distributions could be signposts of embedded planets. The transition disk around the T Tauri star RY Lup has an inner dust cavity and displays a strong silicate emission feature. Aims. Using high-resolution imaging we study the disk geometry, including non-axisymmetric features, and its surface dust grain, to gain a better understanding of the disk evolutionary process. Moreover, we search for companion candidates, possibly connected to the disk. Methods. We obtained high-contrast and high angular resolution data in the near-infrared with the VLT/SPHERE extreme adaptive optics instrument whose goal is to study the planet formation by detecting and characterizing these planets and their formation environments through direct imaging. We performed polarimetric imaging of the RY Lup disk with IRDIS (at 1.6 μm), and obtained intensity images with the IRDIS dual-band imaging camera simultaneously with the IFS spectro-imager (0.9-1.3 μm). Results. We resolved for the first time the scattered light from the nearly edge-on circumstellar disk around RY Lup, at projected separations in the 100 au range. The shape of the disk and its sharp features are clearly detectable at wavelengths ranging from 0.9 to 1.6 μm. We show that the observed morphology can be interpreted as spiral arms in the disk. This interpretation is supported by in-depth numerical simulations. We also demonstrate that these features can be produced by one planet interacting with the disk. We also detect several point sources which are classified as probable background objects. © 2018 ESO. Acknowledgements. We acknowledge our anonymous reviewers for the very careful reading and constructive suggestions that contributed to improving this paper. SPHERE is an instrument designed and built by a consortium consisting of IPAG (Grenoble, France), MPIA (Heidelberg, Germany), LAM (Marseille, France), LESIA (Paris, France), Laboratoire Lagrange (Nice, France), INAF–Osservatorio di Padova (Italy), Observatoire astronomique de l’universite de Geneve (Switzerland), ETH Zurich (Switzerland), NOVA (Netherlands), ONERA (France), and ASTRON (Netherlands) in collaboration with ESO. SPHERE was funded by ESO, with additional contributions from CNRS (France), MPIA (Germany), INAF (Italy), FINES (Switzerland), and NOVA (Netherlands). SPHERE also received funding from the European Commission Sixth and Seventh Framework Programmes as part of the Optical Infrared Coordination Network for Astronomy (OPTICON) under grant number RII3-Ct-2004-001566 for FP6 (2004-2008), grant number 226604 for FP7 (2009-2012), and grant number 312430 for FP7 (2013-2016). This work was supported by the Programme National de Planétologie (PNP) and the Programme National de Physique Stellaire (PNPS) of CNRS-INSU co-funded by CNES. This work has also been supported by a grant from the French Labex OSUG2020 (Investisse-ments d’avenir - ANR10 LABX56) and by the ANR grant ANR-14-CE33-0018 (GIPSE). This work has made use of the SPHERE Data Centre, jointly operated by OSUG/IPAG (Grenoble), PYTHEAS /LAM/CeSAM (Marseille), OCA/Lagrange (Nice), and Observatoire de Paris/LESIA (Paris). This research has made use of the VizieR catalogue access tool, CDS, Strasbourg, France. Q. Kral also acknowledges support from STFC (consolidated grant) via the institute of Asronomy, Cambridge.
Published: 2018

26. Orbital and atmospheric characterization of the planet within the gap of the PDS 70 transition disk

Author: Anne-Lise Maire, Hervé Beust, Th. Henning, Daniel Rouan, Anthony Boccaletti, Alice Zurlo, Jean-Loup Baudino, Janis Hagelberg, Francois Menard, N. Pawellek, Benjamin Charnay, Karan Molaverdikhani, P. Mollière, Faustine Cantalloube, Maud Langlois, Gael Chauvin, L. Weber, Myriam Benisty, Zahed Wahhaj, Eric Stadler, E. Sissa, Anthony Cheetham, Michael Meyer, Matthias Samland, M. Feldt, André Müller, R. van Boekel, Miriam Keppler, Z. C. Long, Dino Mesa, M. Bonnefoy, R. Ligi, Christoph Mordasini, C. Lazzoni, Joany Andreina Manjarres Ramos, R. G. Gratton, Julien Girard, Thierry Fusco, Arthur Vigan, A. Pavlov, Sascha P. Quanz, Anne-Marie Lagrange, Thibaut Moulin, M. Gennaro, Silvano Desidera, Markus Janson, Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Universidad de Santiago de Chile [Santiago] (USACH), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), University of Oxford [Oxford], Space Telescope Science Institute (STSci), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), DOTA, ONERA, Université Paris Saclay (COmUE) [Châtillon], ONERA-Université Paris Saclay (COmUE), Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Institute for Particle Physics and Astrophysics [ETH Zürich] (IPA), Department of Physics [ETH Zürich] (D-PHYS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Stockholm University, Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), INAF - Osservatorio Astronomico di Brera (OAB), Instituto de Astronomia y ciencias Planetarias de Atacama (INCT), Universidad de Atacama, University of Michigan [Ann Arbor], University of Michigan System, Leiden Observatory [Leiden], Universiteit Leiden [Leiden], Universität Bern [Bern], Research Centre for Astronomy and Earth Sciences [Budapest], Hungarian Academy of Sciences (MTA), European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), Universidad Diego Portales [Santiago] (UDP), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), DOTA, ONERA, Université Paris Saclay [Châtillon], ONERA-Université Paris-Saclay, Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich)-Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Pawellek, Nicole [0000-0002-9385-9820], Apollo - University of Cambridge Repository, University of Oxford, Université de Genève = University of Geneva (UNIGE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Universiteit Leiden, Universität Bern [Bern] (UNIBE), ANR-16-CE31-0013,PLANET-FORMING-DISKS,De meilleurs modèles pour de meilleures données(2016), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Laboratoire Franco-Chilien d'Astronomie, UMI 3386, Pôle Planétologie du LESIA, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Department of Physics, University of Oxford, Oxford, UK, Space Telescope Science Institute (STScI), Geneva Observatory, University of Geneva, Chemin des Mailettes 51, 1290, Versoix, Switzerland, INAF-Osservatorio Astronomico di Padova, ONERA, Institute for Astronomy, Department of Physics, ETH Zürich, INAF-Osservatorio Astronomico di Brera (INAF-OAB), Leiden Observatory, Physikalisches Institut, Universitat Bern, Gesellschaftsstrasse 6, 3012, Bern, Switzerland, European Southern Observatory, and Nucleo de Astronomia, Facultad de Ingenieria y Ciencias, Universidad Diego Portales, Av. Ejercito 441, Santiago, Chile
Subjects: 010504 meteorology & atmospheric sciences, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], FOS: Physical sciences, Context (language use), Astrophysics, 01 natural sciences, Planet, 0103 physical sciences, planets and satellites: individual: PDS 70, Astrophysics::Solar and Stellar Astrophysics, Circular orbit, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Physics, planets and satellites: atmospheres, Earth and Planetary Astrophysics (astro-ph.EP), Atmospheric models, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Astronomy and Astrophysics, Astrometry, Orbit, 13. Climate action, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Orbital motion, Spectral energy distribution, astrometry, Astrophysics::Earth and Planetary Astrophysics, methods: observational, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], techniques: spectroscopic, Astrophysics - Earth and Planetary Astrophysics
Abstract: Aims: We aim to characterize the orbital and atmospheric properties of PDS 70 b, which was first identified on May 2015 in the course of the SHINE survey with SPHERE, the extreme adaptive-optics instrument at the VLT. Methods: We obtained new deep SPHERE/IRDIS imaging and SPHERE/IFS spectroscopic observations of PDS 70 b. The astrometric baseline now covers 6 years which allows us to perform an orbital analysis. For the first time, we present spectrophotometry of the young planet which covers almost the entire near-infrared range (0.96 to 3.8 micrometer). We use different atmospheric models covering a large parameter space in temperature, log(g), chemical composition, and cloud properties to characterize the properties of the atmosphere of PDS 70 b. Results: PDS 70 b is most likely orbiting the star on a circular and disk coplanar orbit at ~22 au inside the gap of the disk. We find a range of models that can describe the spectrophotometric data reasonably well in the temperature range between 1000-1600 K and log(g) no larger than 3.5 dex. The planet radius covers a relatively large range between 1.4 and 3.7 R_jupiter with the larger radii being higher than expected from planet evolution models for the age of the planet of 5.4 Myr. Conclusions: This study provides a comprehensive dataset on the orbital motion of PDS 70 b, indicating a circular orbit and a motion coplanar with the disk. The first detailed spectral energy distribution of PDS 70 b indicates a temperature typical for young giant planets. The detailed atmospheric analysis indicates that a circumplanetary disk may contribute to the total planet flux., Comment: accepted for publication in A&A (10 pages, 8 figures)
Published: 2018
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27. VLT/SPHERE astrometric confirmation and orbital analysis of the brown dwarf companion HR 2562 B

Author: Anne-Lise Maire, Hervé Beust, Anne-Marie Lagrange, Daniel Rouan, D. Perret, Stéphane Udry, Miriam Keppler, S. Daemgen, Michael Meyer, M. Feldt, Arthur Vigan, D. Maurel, Thomas Henning, L. Rodet, R. G. Gratton, J. C. Augereau, Hubert Klahr, C. Petit, Johan Olofsson, A. Delboulbe, Philippe Thébault, Silvano Desidera, R. Ligi, Maud Langlois, Wolfgang Brandner, Faustine Cantalloube, Valentina D'Orazi, A. Roux, Mickael Bonnefoy, Jose Ramos, Thibaut Moulin, L. Abe, Janis Hagelberg, L. Weber, Dino Mesa, M. Carle, H. Le Coroller, Anthony Boccaletti, Matthias Samland, A. Zurlo, Raphaël Galicher, A. Pavlov, Philippe Feautrier, Markus Janson, T. Schmidt, Yves Magnard, C. Lazzoni, Gael Chauvin, F. Rigal, Max-Planck-Institut für Astronomie (MPIA), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), Dipartimento di Fisica e Astronomia G. Galilei, Università di Padova, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), INCT, Universidad de Atacama, calle Copayapu 485, Copiapo, Atacama, Chile, Laboratoire Franco-Chilien d'Astronomie, UMI 3386, Department of Astronomy, Stockholm University, AlbaNova University Center, 106 91, Stockholm, Sweden, Departamento de Física y Astronomía, Universidad de Valparaiso, Institute for Astronomy, Department of Physics, ETH Zürich, Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), University of Michigan, INAF - Osservatorio Astronomico di Brera (OAB), ISDC, Geneva Observatory, University of Geneva, Nucleo de Astronomia, Facultad de Ingenieria, Universidad Diego Portales, Avenida Ejercito 441, Santiago, Chile, Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA), ONERA - The French Aerospace Lab [Palaiseau], ONERA-Université Paris Saclay (COmUE), Astronomical Institute Anton Pannekoek, University of Amsterdam, Max-Planck-Gesellschaft, Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Dipartimento di Fisica e Astronomia 'Galileo Galilei', Università degli Studi di Padova = University of Padua (Unipd), Instituto de Astronomia y ciencias Planetarias de Atacama (INCT), Universidad de Atacama, Laboratoire Franco-Chilien d'Astronomie (LFCA), Universidad de Chile = University of Chile [Santiago] (UCHILE)-Pontificia Universidad Católica de Chile (UC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Universidad de Concepción - University of Concepcion [Chile], Stockholm University, Universidad de Valparaiso [Chile], Institute of Astronomy [ETH Zürich], Department of Physics [ETH Zürich] (D-PHYS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), University of Michigan [Ann Arbor], University of Michigan System, Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève = University of Geneva (UNIGE), Universidad Diego Portales [Santiago] (UDP), Universidad de Chile = University of Chile [Santiago] (UCHILE), Observatoire de la Côte d'Azur (OCA), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), DOTA, ONERA, Université Paris Saclay (COmUE) [Palaiseau], Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Universita degli Studi di Padova, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Universidad de Concepción [Chile]-Pontificia Universidad Católica de Chile (UC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Universidad de Chile, Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich)-Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Université de Genève (UNIGE), Universidad de Chile, Centre National de la Recherche Scientifique (CNRS), DOTA, ONERA, Université Paris Saclay [Palaiseau], ONERA-Université Paris-Saclay, Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), and Université Paris Saclay (COmUE)-ONERA
Subjects: 010504 meteorology & atmospheric sciences, BROWN DWARFS, Brown dwarf, FOS: Physical sciences, METHODS: DATA ANALYSIS, Astrophysics, 01 natural sciences, [SPI]Engineering Sciences [physics], 0103 physical sciences, TECHNIQUES: IMAGE PROCESSING, Coordination network, Astrophysics::Solar and Stellar Astrophysics, European commission, STARS: INDIVIDUAL: HR 2562, 010303 astronomy & astrophysics, Orbital analysis, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Earth and Planetary Astrophysics (astro-ph.EP), Physics, [PHYS]Physics [physics], Astronomy and Astrophysics, PLANETS AND SATELLITES: DYNAMICAL EVOLUTION AND STABILITY, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, TECHNIQUES: HIGH ANGULAR RESOLUTION, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Earth and Planetary Astrophysics
Abstract: Context. A low-mass brown dwarf has been recently imaged around HR 2562 (HD 50571), a star hosting a debris disk resolved in the far infrared. Interestingly, the companion location is compatible with an orbit coplanar with the disk and interior to the debris belt. This feature makes the system a valuable laboratory to analyze the formation of substellar companions in a circumstellar disk and potential disk-companion dynamical interactions. Aims. We aim to further characterize the orbital motion of HR 2562 B and its interactions with the host star debris disk. Methods. We performed a monitoring of the system over ~10 months in 2016 and 2017 with the VLT/SPHERE exoplanet imager. Results. We confirm that the companion is comoving with the star and detect for the first time an orbital motion at high significance, with a current orbital motion projected in the plane of the sky of 25 mas (~0.85 au) per year. No orbital curvature is seen in the measurements. An orbital fit of the SPHERE and literature astrometry of the companion without priors on the orbital plane clearly indicates that its orbit is (quasi-)coplanar with the disk. To further constrain the other orbital parameters, we used empirical laws for a companion chaotic zone validated by N-body simulations to test the orbital solutions that are compatible with the estimated disk cavity size. Non-zero eccentricities (>0.15) are allowed for orbital periods shorter than 100 yr, while only moderate eccentricities up to ~0.3 for orbital periods longer than 200 yr are compatible with the disk observations. A comparison of synthetic Herschel images to the real data does not allow us to constrain the upper eccentricity of the companion., Accepted for publication in A&A. 14 pages, 14 figures, 3 tables. Updated to match published paper. Bug in the computation of the distributions of times at periastron passages corrected, minor effects on other orbital parameters
Published: 2018

28. Exploring the realm of scaled solar system analogues with HARPS

Author: Alessandro Sozzetti, D. Barbato, Riccardo Claudi, C. Lazzoni, G. LoCurto, Paolo Giacobbe, Mario Damasso, Silvano Desidera, Christoph Mordasini, Aldo S. Bonomo, L. S. Colombo, R. G. Gratton, and Francesco Marzari
Subjects: Solar System, 010504 meteorology & atmospheric sciences, Exoplanetology, FOS: Physical sciences, Astrophysics, 01 natural sciences, Planet, 0103 physical sciences, techniques: radial velocities, stars: individual: HD 50499, 010303 astronomy & astrophysics, planetary systems, 0105 earth and related environmental sciences, methods: data analysis, stars: individual: HD 73267, Physics, Orbital elements, Earth and Planetary Astrophysics (astro-ph.EP), Giant planet, Astronomy and Astrophysics, Planetary system, Methods: data analysis, Planetary systems, Stars: individual: HD 50499, Stars: individual: HD 73267, Techniques: radial velocities, Space and Planetary Science, Stars, Astrophysics::Earth and Planetary Astrophysics, Low Mass, Astrophysics - Earth and Planetary Astrophysics
Abstract: The assessment of the frequency of planetary systems reproducing the Solar System's architecture is still an open problem. Detailed study of multiplicity and architecture is generally hampered by limitations in quality, temporal extension and observing strategy, causing difficulties in detecting low-mass inner planets in the presence of outer giant planetary bodies. We present the results of high-cadence and high-precision HARPS observations on 20 solar-type stars known to host a single long-period giant planet in order to search for additional inner companions and estimate the occurence rate $f_p$ of scaled Solar System analogs, i.e. systems featuring lower-mass inner planets in the presence of long-period giant planets. We carry out combined fits of our HARPS data with literature radial velocities using differential evolution MCMC to refine the literature orbital solutions and search for additional inner planets. We then derive the survey detection limits to provide preliminary estimates of $f_p$. We generally find better constrained orbital parameters for the known planets than those found in the literature. While no additional inner planet is detected, we find evidence for previously unreported long-period massive companions in systems HD 50499 and HD 73267. We finally estimate the frequency of inner low mass (10-30 M$_\oplus$) planets in the presence of outer giant planets as $f_p, 32 pages, 27 figures, accepted for publication in A&A
Published: 2018

29. In-depth study of moderately young but extremely red, very dusty substellar companion HD 206893B

Author: Olivier Absil, Anne-Marie Lagrange, Alice Zurlo, Franz-Josef Hambsch, J. L. Beuzit, P. W. Lucas, C. Petit, Th. Henning, Anne-Lise Maire, Mickael Bonnefoy, Daniel Rouan, Norbert Hubin, T. Schmidt, Francois Wildi, Christian Ginski, L. Rodet, Julien Milli, Joshua E. Schlieder, Mariangela Bonavita, Johan Olofsson, A. Pavlov, Valentina D'Orazi, Joseph C. Carson, C. Mordasini, Anthony Cheetham, Elvira Covino, Janis Hagelberg, Raphaël Galicher, Julien Girard, Baptiste Lavie, Valentin Christiaens, M. Feldt, Anthony Boccaletti, Gael Chauvin, David Mouillet, C. Lazzoni, Federico Marocco, Stéphane Udry, Benjamin Charnay, Sergio Messina, Silvano Desidera, Arthur Vigan, Ronald Roelfsema, R. G. Gratton, A. Delboulbe, Beth Biller, Faustine Cantalloube, Maud Langlois, V. De Caprio, Philippe Delorme, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), Leiden Observatory [Leiden], Universiteit Leiden, Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Departamento de Astronomía, Universidad de Chile = University of Chile [Santiago] (UCHILE), Millenium Nucleus Protoplanetary Disks in ALMA Early Science, Space Sciences, Technologies and Astrophysics Research Institute (STAR), Université de Liège, INAF - Osservatorio Astrofisico di Catania (OACT), Monash University [Melbourne], European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, NASA ExoPlanet Science Institute (NExScI), California Institute of Technology (CALTECH), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), SUPA, Institute for Astronomy, University of Edinburgh, Physikalisches Institut [Bern], Universität Bern [Bern] (UNIBE), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève = University of Geneva (UNIGE), Universidad Diego Portales [Santiago] (UDP), Instituto de Fisica y Astronomia [Valparaiso], Universidad de Valparaiso [Chile], DAAA, ONERA, Université Paris-Saclay [Châtillon], ONERA-Université Paris-Saclay, Remote Observatory Atacama Desert (ROAD), Arizona Materials Laboratory (AML), University of Arizona, Centre for Astrophysics Research [Hatfield], University of Hertfordshire [Hatfield] (UH), College of Charleston, INAF - Osservatorio Astronomico di Capodimonte (OAC), NOVA Optical Infrared Instrumentation Group, ANR-14-CE33-0018,GIPSE,Exploration des planetes géantes extrasolaires(2014), ANR-10-LABX-0056,OSUG@2020,Innovative strategies for observing and modelling natural systems(2010), European Project: 226604,EC:FP7:INFRA,FP7-INFRASTRUCTURES-2008-1,OPTICON(2009), European Project: 312430,EC:FP7:INFRA,FP7-INFRASTRUCTURES-2012-1-RTD,OPTICON(2013), European Project: 337569,EC:FP7:ERC,ERC-2013-StG,VORTEX(2013), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Universiteit Leiden [Leiden], Universidad de Chile, Universität Bern [Bern], Université de Genève (UNIGE), Instituto de Fisica y Astronomia, ONERA - The French Aerospace Lab [Châtillon], ONERA, Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Pôle Planétologie du LESIA, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, INAF-Osservatorio Astronomico di Padova, Leiden Observatory, University of Liège, INAF-Osservatorio Astrofisico di Catania (INAF-OACt), European Southern Observatory, Institute for Astronomy, The University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh, EH9 3HJ, UK, ISDC, Geneva Observatory, University of Geneva, Nucleo de Astronomia, Facultad de Ingenieria, Universidad Diego Portales, Av. Ejercito 441, Santiago, Chile, Remote Observatory Atacama Desert (ROAD), Vereniging Voor Sterrenkunde (VVS), Oude Bleken 12, 2400, Mol, Belgium, Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), University of Bern (UBERN), Centre for Astrophysics Research, Science and Technology Research Institute, University of Hertfordshire, Institute for Astronomy, Blackford Hill, INAF Napoli: INAF, Astrophysical Observatory of Capodimonte, Salita Moiariello 16, 80131, Napoli, Italy, Netherlands Institute for Radio Astronomy (ASTRON), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), and Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES)
Subjects: 010504 meteorology & atmospheric sciences, 530 Physics, Brown dwarf, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Physics, planets and satellites: atmospheres, planet-disk interactions, 520 Astronomy, techniques: high angular resolution, Astronomy and Astrophysics, 500 Science, 620 Engineering, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], brown dwarfs
Abstract: The substellar companion HD206893b has recently been discovered by direct imaging of its disc-bearing host star with the SPHERE instrument. We investigate the atypical properties of the companion, which has the reddest near-infrared colours among all known substellar objects, either orbiting a star or isolated, and we provide a comprehensive characterisation of the host star-disc-companion system. We conducted a follow-up of the companion with adaptive optics imaging and spectro-imaging with SPHERE, and a multiinstrument follow-up of its host star. We obtain a R=30 spectrum from 0.95 to 1.64 micron of the companion and additional photometry at 2.11 and 2.25 micron. We carried out extensive atmosphere model fitting for the companions and the host star in order to derive their age, mass, and metallicity. We found no additional companion in the system in spite of exquisite observing conditions resulting in sensitivity to 6MJup (2MJup) at 0.5" for an age of 300 Myr (50 Myr). We detect orbital motion over more than one year and characterise the possible Keplerian orbits. We constrain the age of the system to a minimum of 50 Myr and a maximum of 700 Myr, and determine that the host-star metallicity is nearly solar. The comparison of the companion spectrum and photometry to model atmospheres indicates that the companion is an extremely dusty late L dwarf, with an intermediate gravity (log g 4.5-5.0) which is compatible with the independent age estimate of the system. Though our best fit corresponds to a brown dwarf of 15-30 MJup aged 100-300 Myr, our analysis is also compatible with a range of masses and ages going from a 50 Myr 12MJup planetary-mass object to a 50 MJup Hyades-age brown dwarf..., Comment: Accepted to A&A
Published: 2017

30. GIARPS@TNG: GIANO-B and HARPS-N together for a wider wavelength range spectroscopy

Author: Elena Suárez González, Luca Malavolta, Nicoletta Sanna, Giuseppina Micela, Carlo Baffa, M. Hernandez Diaz, C. Riverol, Luca Fini, I. Carleo, Andrea Tozzi, Adriano Ghedina, Avet Harutyunyan, Ulf Seemann, José Guerra, Salvo Scuderi, Serena Benatti, Alessandro Sozzetti, Rosario Cosentino, Emilio Molinari, Riccardo Claudi, Monica Rainer, Livia Origlia, Francesca Ghinassi, A. Galli, Daniela Fantinel, Jesus Maldonado, Massimo Cecconi, Concepción Iglesias González, M. Gonzalez, Elisabetta Giani, Marcello Lodi, N. Hernandez, R. G. Gratton, Andrea Baruffolo, J. Sanjuan, H. Perez Ventura, Ernesto Oliva, N. Buchschacher, and L. Riverol
Subjects: Physics, Wavelength range, General Physics and Astronomy, Astronomy, 01 natural sciences, Exoplanet, law.invention, 010309 optics, Telescope, Radial velocity, Stars, Cardinal point, law, 0103 physical sciences, Spectroscopy, 010303 astronomy & astrophysics, Spectrograph
Abstract: Since 2012, thanks to the installation of the high-resolution echelle spectrograph in the optical range HARPS-N, the Italian telescope TNG (La Palma) became one of the key facilities for the study of the extrasolar planets. In 2014 TNG also offered GIANO to the scientific community, providing a near-infrared (NIR) cross-dispersed echelle spectroscopy covering 0.97-2.45μm at a resolution of 50000. GIANO, although designed for direct light-feed from the telescope at the Nasmyth-B focus, was provisionally mounted on the rotating building and connected via fibers to only available interface at the Nasmyth-A focal plane. The synergy between these two instruments is particularly appealing for a wide range of science cases, especially for the search of exoplanets around young and active stars and the characterisation of their atmosphere. Through the funding scheme "WOW" (a Way to Others Worlds), the Italian National Institute for Astrophysics (INAF) proposed to position GIANO at the focal station for which it was originally designed and the simultaneous use of these spectrographs with the aim to achieve high-resolution spectroscopy in a wide wavelength range (0.383-2.45μm) obtained in a single exposure, giving rise to the project called GIARPS (GIANO-B & HARPS-N). Because of its characteristics, GIARPS can be considered the first and unique worldwide instrument providing not only high resolution in a large wavelength band, but also a high-precision radial velocity measurement both in the visible and in the NIR arm, since in the next future GIANO-B will be equipped with gas absorption cells.
Published: 2017

31. SPHERE/ZIMPOL observations of the symbiotic system R: I. Imaging of the stellar binary and the innermost jet clouds

Author: C. Thalmann, J. L. Beuzit, J. H. Girard, Bernardo Salasnich, David Mouillet, H. M. Schmid, Silvano Desidera, M. Feldt, Kjetil Dohlen, F. Joos, M. Kasper, Marcos Suarez, N. Engler, Andrea Baruffolo, Eric Lagadec, Stéphane Udry, Norbert Hubin, J.-F. Sauvage, Maud Langlois, Pascal Puget, Julien Milli, M. Stute, A. Pavlov, Anne Costille, A. Boccaletti, Francois Wildi, Riccardo Claudi, Ch. Ginski, Judit Szulágyi, Ralf Siebenmorgen, Arthur Vigan, Sascha P. Quanz, T. Fusco, R. G. Gratton, Alexander J. Bohn, E. Sissa, Andreas Bazzon, J. Pragt, Carsten Dominik, Th. Henning, R. Roelfsema, Massimo Turatto, D. Gisler, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), ONERA - The French Aerospace Lab [Châtillon], ONERA, European Project: RII3-Ct-2004-001566 ,OPTICON, European Project: 226604,EC:FP7:INFRA,FP7-INFRASTRUCTURES-2008-1,OPTICON(2009), European Project: 312430,EC:FP7:INFRA,FP7-INFRASTRUCTURES-2012-1-RTD,OPTICON(2013), Low Energy Astrophysics (API, FNWI), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), ONERA-Université Paris Saclay (COmUE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Institute for Astronomy, Department of Physics, ETH Zürich, European Southern Observatory, Netherlands Institute for Radio Astronomy (ASTRON), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, INAF-Osservatorio Astronomico di Padova, Leiden Observatory, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Astronomical Institute Anton Pannekoek, University of Amsterdam, Max-Planck-Institut für Astronomie (MPIA), Kiepenheuer-Institut für Sonnenphysik (KIS), European Southern Observatory (ESO), Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Astrium, Geneva Observatory, University of Geneva, Chemin des Mailettes 51, 1290, Versoix, Switzerland, ITA, FRA, DEU, NLD, CHE, Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, and Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Orbital plane, Red giant, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Outflows, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Winds, 01 natural sciences, 010309 optics, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Emission spectrum, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, Line (formation), Physics, Nebula, Very Large Telescope, Jet (fluid), Mira variable, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Instrumentation: adaptive optics, Binaries: symbiotic, Astronomy and Astrophysics, Circumstellar matter, Stars, individual: R Aqr, binaries: symbiotic, Stars: winds, outflows, Instrumentation: adaptive optics [stars], Stars: individual: R Aqr, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: R Aqr is a symbiotic binary system consisting of a mira variable, a hot companion with a spectacular jet outflow, and an extended emission line nebula. We have used R Aqr as test target for the visual camera subsystem ZIMPOL, which is part of the new extreme adaptive optics (AO) instrument SPHERE at the Very Large Telescope (VLT). We compare our observations with data from the Hubble Space Telescope (HST) and illustrate the complementarity of the two instruments. We determine from the Halpha emission the position, size, geometric structure, and line fluxes of the jet source and the clouds in the innermost region (, 24 pages, 14 figures (accepted for publication in Astronomy and Astrophysics)
Published: 2017

32. Upper limits for mass and radius of objects around Proxima Cen from SPHERE/VLT

Author: Julien Milli, S. Incorvaia, Eric Lagadec, Alice Zurlo, Riccardo Claudi, Arthur Vigan, G. Farisato, Jacopo Antichi, Massimo Turatto, H. M. Schmid, Michael Meyer, E. Sissa, Daniela Fantinel, Luigi Lessio, Clément Perrot, Janis Hagelberg, Beth Biller, Quentin Kral, Enrico Giro, Anne-Marie Lagrange, Andrea Baruffolo, Salvo Scuderi, Silvano Desidera, Anthony Boccaletti, Joshua E. Schlieder, Pietro Bruno, Mariangela Bonavita, Enrico Cascone, S. Peretti, Julien Girard, R. G. Gratton, Gael Chauvin, Markus Janson, C. Thalmann, Bernardo Salasnich, Maud Langlois, V. De Caprio, Dino Mesa, Henning Avenhaus, Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), and Apollo - University of Cambridge Repository
Subjects: FOS: Physical sciences, 01 natural sciences, 7. Clean energy, Planet, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, planetary systems, 010303 astronomy & astrophysics, Spectrograph, Instrumentation and Methods for Astrophysics (astro-ph.IM), Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, instrumentation: spectrographs, Physics, Earth and Planetary Astrophysics (astro-ph.EP), Very Large Telescope, 010308 nuclear & particles physics, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astronomy and Astrophysics, Radius, Astrometry, Planetary system, methods: data analysis, Exoplanet, Radial velocity, Astrophysics - Solar and Stellar Astrophysics, techniques: imaging spectroscopy, 13. Climate action, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, [SDU.ASTR.GA]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], stars: individual: Proxima Centauri, Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract: The recent discovery of an earth-like planet around Proxima Centauri has drawn much attention to this star and its environment. We performed a series of observations of Proxima Centauri using SPHERE, the planet finder instrument installed at the ESO Very Large Telescope UT3, using its near infrared modules, IRDIS and IFS. No planet was directly detected but we set upper limits on the mass up to 7 au exploiting the AMES-COND models. Our IFS observations reveal that no planet more massive than ~6-7 M Jup can be present within 1 au. The dual band imaging camera IRDIS also enables us to probe larger separations than the other techniques like the radial velocity or astrometry. We obtained mass limits of the order of 4 M Jup at separations of 2 au or larger representing the most stringent mass limits at separations larger than 5 au available at the moment. We also did an attempt to estimate the radius of possible planets around Proxima using the reflected light. Since the residual noise for this observations are dominated by photon noise and thermal background, longer exposures in good observing conditions could further improve the achievable contrast limit., Comment: 5 pages, 4 figures, accepted by MNRAS
Published: 2017

33. HADES RV Programme with HARPS-N at TNG. IV. Time resolved analysis of the Ca II H&K and Hα chromospheric emission of low-activity early-type M dwarfs

Author: A. Rosich, Riccardo Claudi, E. González Álvarez, Jesus Maldonado, Antonio Maggio, Giampaolo Piotto, Giuseppina Micela, Beate Stelzer, Sergio Messina, Alessandro Sozzetti, R. Zanmar Sanchez, A. Suárez Mascareño, Rafael Rebolo, Giuseppe Leto, Katia Biazzo, Manuel Perger, Rosario Cosentino, A. F. Lanza, Gaetano Scandariato, Ignasi Ribas, J. I. González Hernández, R. G. Gratton, Mario Damasso, Isabella Pagano, Silvano Desidera, Laura Affer, ITA, and ESP
Subjects: Rotation period, Physics, 010504 meteorology & atmospheric sciences, Astronomy and Astrophysics, Context (language use), Astrophysics, 01 natural sciences, K-line, Spectral line, Stars, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, 0103 physical sciences, Terrestrial planet, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, 010303 astronomy & astrophysics, Circumstellar habitable zone, 0105 earth and related environmental sciences, Line (formation)
Abstract: Context. M dwarfs are prime targets for current and future planet search programs, particularly those focused on the detection and characterization of rocky planets in the habitable zone. In this context, understanding their magnetic activity is important for two main reasons: it affects our ability to detect small planets and it plays a key role in the characterization of the stellar environment. Aims: We analyze observations of the Ca II H&K and Hα lines as diagnostics of chromospheric activity for low-activity early-type M dwarfs. Methods: We analyze the time series of spectra of 71 early-type M dwarfs collected in the framework of the HADES project for planet search purposes. The HARPS-N spectra simultaneously provide the Ca II H&K doublet and the Hα line. We develop a reduction scheme able to correct the HARPS-N spectra for instrumental and atmospheric effects, and also to provide flux-calibrated spectra in units of flux at the stellar surface. The Ca II H&K and Hα fluxes are then compared with each other, and their time variability is analyzed. Results: We find that the Ca II H and K flux excesses are strongly correlated with each other, while the Hα flux excess is generally less correlated with the Ca II H&K doublet. We also find that Hα emission does not increase monotonically with the Ca II H&K line flux, showing some absorption before being filled in by chromospheric emission when Ca II H&K activity increases. Analyzing the time variability of the emission fluxes, we derive a tentative estimate of the rotation period (on the order of a few tens of days) for some of the program stars, and the typical lifetime of chromospheric active regions (on the order of a few stellar rotations). Conclusions: Our results are in good agreement with similar previous studies. In particular, we find evidence that the chromospheres of early-type M dwarfs could be characterized by different filament coverage, affecting the formation mechanism of the Hα line. We also show that chromospheric structure is likely related to spectral type.
Published: 2017

34. New constraints on the disk characteristics and companion candidates around T Chamaeleontis with VLT/SPHERE

Author: Th. Henning, E. Sissa, R. van Boekel, André Müller, Silvano Desidera, C. Perrot, Anne-Marie Lagrange, Anne-Lise Maire, Sebastian Daemgen, Johan Olofsson, Alice Zurlo, Gael Chauvin, Antonio Garufi, Beth Biller, Ch. Ginski, R. G. van Holstein, Dino Mesa, Arthur Vigan, R. G. Gratton, Maud Langlois, Tomas Stolker, M. Cudel, Myriam Benisty, Francois Menard, Judit Szulágyi, M. Kasper, J. de Boer, Carsten Dominik, Francois Wildi, Markus Janson, Anthony Cheetham, Christophe Pinte, Quentin Kral, M. Feldt, Anthony Boccaletti, A. Pohl, Mickael Bonnefoy, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), ANR-16-CE31-0013,PLANET-FORMING-DISKS,De meilleurs modèles pour de meilleures données(2016), Max-Planck-Institut für Astronomie (MPIA), INAF-Osservatorio Astronomico di Padova, Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Leiden Observatory, Departamento de Física y Astronomía, Universidad de Valparaiso, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Institute for Astronomy, Department of Physics, ETH Zürich, Astronomical Institute Anton Pannekoek, University of Amsterdam, Institute of Astronomy, University of Cambridge (IoA), Nucleo de Astronomia, Facultad de Ingenieria, Universidad Diego Portales, Av. Ejercito 441, Santiago, Chile, Observatoire astronomique de l'Universite de Geneve, 51 ch. des Maillettes, 1290, Versoix, Switzerland, European Southern Observatory (ESO), and Low Energy Astrophysics (API, FNWI)
Subjects: Physics, Earth and Planetary Astrophysics (astro-ph.EP), [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Astronomy, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, 01 natural sciences, 010309 optics, 13. Climate action, Space and Planetary Science, 0103 physical sciences, Coordination network, Astrophysics::Solar and Stellar Astrophysics, Christian ministry, European commission, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract: The transition disk around the T Tauri star T Cha possesses a large gap, making it a prime target for high-resolution imaging in the context of planet formation. We aim to find signs of disk evolutionary processes by studying the disk geometry and the dust grain properties at its surface, and to search for companion candidates. We analyze a set of VLT/SPHERE data at near-infrared and optical wavelengths. We performed polarimetric imaging of T Cha with IRDIS (1.6 $\mu$m) and ZIMPOL (0.5-0.9 $\mu$m), and obtained intensity images from IRDIS dual-band imaging with simultaneous spectro-imaging with IFS (0.9-1.3 $\mu$m). The disk around T Cha is detected in all observing modes and its outer disk is resolved in scattered light with unprecedented angular resolution and signal-to-noise. The images reveal a highly inclined disk with a noticeable east-west brightness asymmetry. The significant amount of non-azimuthal polarization signal in the $U_{\phi}$ images, with a $U_{\phi}$/$Q_{\phi}$ peak-to-peak value of 14%, is in accordance with theoretical studies on multiple scattering. Our optimal axisymmetric radiative transfer model considers two coplanar inner and outer disks, separated by a gap of 0.28" (~30au) in size. We derive a disk inclination of ~69 deg and PA of ~114 deg. In order to self-consistently reproduce the intensity and polarimetric images, the dust grains, responsible for the scattered light, need to be dominated by sizes of around ten microns. A point source is detected at an angular distance of 3.5" from the central star. It is, however, found not to be co-moving. We confirm that the dominant source of emission is forward scattered light from the near edge of the outer disk. Our point source analysis rules out the presence of a companion heavier than ~8.5 $M_{\mathrm{jup}}$ between 0.1" and 0.3". The detection limit decreases to ~2 $M_{\mathrm{jup}}$ for 0.3" to 4.0"., Comment: 17 pages, 14 figures, accepted for publication in A&A. Revised version after language editing
Published: 2017

35. A stellar population synthesis approach to the Oosterhoff dichotomy

Author: Santi Cassisi, R. G. Gratton, Giuliana Fiorentino, and Antonio Sollima
Subjects: Physics, Stellar population, Milky Way, Metallicity, FOS: Physical sciences, Astronomy, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Horizontal branch, RR Lyrae variable, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Globular cluster, Cluster (physics), Astrophysics::Solar and Stellar Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, Dwarf galaxy
Abstract: We use color-magnitude diagram synthesis together with theoretical relations from non-linear pulsation models to approach the long-standing problem of the Oosterhoff dichotomy related to the distribution of the mean periods of fundamental RR Lyrae variables in globular clusters. By adopting the chemical composition determined from spectroscopic observations and a criterion to account for the hysteresis mechanism, we tuned age and mass-loss to simultaneously reproduce the morphology of both the turn-off and the Horizontal Branch of a sample of 17 globular clusters of the Milky Way and of nearby dwarf galaxies in the crucial metallicity range (-1.9, Comment: 12 pages, 7 figures, accepted for publication by MNRAS
Published: 2014

36. GIARPS: the unique VIS-NIR high precision radial velocity facility in this world

Author: José Guerra, I. Carleo, A. Galli, C. Riverol, L. Riverol, Adriano Ghedina, Andrea Baruffolo, Marcello Lodi, Emilio Molinari, Riccardo Claudi, Rosario Cosentino, N. Hernandez, J. Sanjuan, M. Iuzzolino, Carlos Gonzalez, Giuseppina Micela, Ernesto Oliva, H. Diaz Marcos, Nicoletta Sanna, Luca Fini, Salvo Scuderi, R. G. Gratton, Daniela Fantinel, Luca Malavolta, Manuel Gonzalez, Jesus Maldonado, Serena Benatti, Alessandro Sozzetti, Massimo Cecconi, H. PÃ©rez Ventura, Francesca Ghinassi, Andrea Tozzi, and Avet Harutyunyan
Subjects: 010504 meteorology & atmospheric sciences, Young stellar object, FOS: Physical sciences, 01 natural sciences, Planet, 0103 physical sciences, Hot Jupiter, Electronic, Astrophysics::Solar and Stellar Astrophysics, Optical and Magnetic Materials, Electrical and Electronic Engineering, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Physics, Design reports on new instrumentation, Exoplanet Instruments, Electronic, Optical and Magnetic Materials, Condensed Matter Physics, Applied Mathematics, Near-infrared spectroscopy, Astronomy, Exoplanet, Galaxy, Radial velocity, Stars, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: GIARPS (GIAno & haRPS) is a project devoted to have on the same focal station of the Telescopio Nazionale Galileo (TNG) both the high resolution spectrographs HARPS-N (VIS) and GIANO (NIR) working simultaneously. This could be considered the first and unique worldwide instrument providing cross-dispersed echelle spectroscopy at a high resolution (R=115,000 in the visual and R=50,000 in the IR) and over in a wide spectral range (0.383 - 2.45 micron) in a single exposure. The science case is very broad, given the versatility of such an instrument and the large wavelength range. A number of outstanding science cases encompassing mainly extra-solar planet science starting from rocky planet search and hot Jupiters, atmosphere characterization can be considered. Furthermore both instrument can measure high precision radial velocity by means the simultaneous thorium technique (HARPS - N) and absorbing cell technique (GIANO) in a single exposure. Other science cases are also possible. Young stars and proto-planetary disks, cool stars and stellar populations, moving minor bodies in the solar system, bursting young stellar objects, cataclysmic variables and X-ray binary transients in our Galaxy, supernovae up to gamma-ray bursts in the very distant and young Universe, can take advantage of the unicity of this facility both in terms of contemporaneous wide wavelength range and high resolution spectroscopy., 8 pages, 5 figures, SPIE Conference Proceedings
Published: 2016

37. The HADES RV Programme with HARPS-N@TNG. III. Flux-flux and activity-rotation relationships of early-M dwarfs

Author: Jesus Maldonado, R. Zanmar Sanchez, Isabella Pagano, A. F. Lanza, Gaetano Scandariato, R. G. Gratton, Alessandro Sozzetti, Giuseppina Micela, Mario Damasso, Antonio Maggio, Katia Biazzo, Giampaolo Piotto, Riccardo Claudi, Sergio Messina, Manuel Perger, Ignasi Ribas, Emilio Molinari, Beate Stelzer, A. Suárez Mascareño, Rafael Rebolo, Giuseppe Leto, Silvano Desidera, E. González Álvarez, Rosario Cosentino, J. I. González Hernández, and Laura Affer
Subjects: Red dwarf, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Context (language use), Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, symbols.namesake, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, Physics, 010308 nuclear & particles physics, Stellar atmosphere, Balmer series, Astronomy and Astrophysics, Effective temperature, Exoplanet, Radial velocity, Stars, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, symbols, Astrophysics::Earth and Planetary Astrophysics
Abstract: (Abridged) Understanding stellar activity in M dwarfs is crucial for the physics of stellar atmospheres as well as for ongoing radial velocity exoplanet programmes. Despite the increasing interest in M dwarfs, our knowledge of the chromospheres of these stars is far from being complete. We aim to test whether the relations between activity, rotation, and stellar parameters and flux-flux relationships also hold for early-M dwarfs on the main-sequence. We analyse in an homogeneous and coherent way a well defined sample of 71 late-K/early-M dwarfs that are currently being observed in the framework of the HArps-n red Dwarf Exoplanet Survey (HADES). Rotational velocities are derived using the cross-correlation technique while emission flux excesses in the Ca II H & K and Balmer lines from Halpha up to Hepsilon are obtained by using the spectral subtraction technique. The relationships between the emission excesses and the stellar parameters are studied. Relations between pairs of fluxes of different chromospheric lines are also studied. We find that the strength of the chromospheric emission in the Ca II H & K and Balmer lines is roughly constant for stars in the M0-M3 spectral range. Our data suggest that a moderate but significant correlation between activity and rotation might be present as well as a hint of kinematically selected young stars showing higher levels of emission. We find our sample of M dwarfs to be complementary in terms of chromospheric and X-ray fluxes with those of the literature, extending the analysis of the flux-flux relationships to the very low flux domain. Our results agree with previous works suggesting that the activity-rotation-age relationship known to hold for solar-type stars also applies to early-M dwarfs. We also confirm previous findings that the field stars which deviate from the bulk of the empirical flux-flux relationships show evidence of youth., Accepted for publication by Astronomy & Astrophysics, This version: some typos corrected
Published: 2016

38. Pushing down with the contrast: scientific performances with SPHERE-IFS

Author: Pascal Puget, Norbert Hubin, Bernardo Salasnich, Maud Langlois, G. Farisato, Julien Girard, Anne-Lise Maire, Enrico Giro, Andrea Baruffolo, Daniela Fantinel, E. Sissa, Salvo Scuderi, Dino Mesa, V. Decaprio, R. G. Gratton, Riccardo Claudi, A. Boccaletti, Jacopo Antichi, A. Zurlo, Luigi Lessio, Gael Chauvin, David Mouillet, Francois Wildi, J. L. Lizon, Enrico Cascone, Kjetil Dohlen, Glenn Finger, Massimo Turatto, J. L. Beuzit, Silvano Desidera, Valentina D'Orazi, Patrick Bruno, M. Kasper, and M. Depascale
Subjects: Scientific instrument, Physics, Near-infrared spectroscopy, Polarimetry, Field of view, Astrophysics, 01 natural sciences, Exoplanet, Stars, Integral field spectrograph, K band, 0103 physical sciences, 010306 general physics, 010303 astronomy & astrophysics
Abstract: The VLT second generation instrument SPHERE (Spectro-Polarimetric High-contrast Exoplanets Research) was commissioned in the Summer of 2014, and offered to the community in the Spring of 2015. SPHERE is a high contrast imager that exploits its three scientific channels in order to observe and discover young warm exoplanets in the glare of their host stars. The three scientific instrument are: ZIMPOL, a polarization analyzer and imager that works in the visible range of wavelength, IRDIS a dual band imager and spectro polarimetric Camera that works in the NIR range up to K band, and IFS, an integral field spectrograph working in the YJH band. Very important is the complementarity between IRDIS and IFS. The former has a larger Field of view (about 12 arcseconds) while the IFS push its examination very close to the central star (FoV ~ 1.7 arcsec). In one year of operational time a lot of very interesting scientific cases were investigated and very nice results were gathered. In this paper we would like to focus the attention on the high quality results and performances obtained with the IFS.
Published: 2016

39. EPICS, the exoplanet imager for the E-ELT

Author: H. M. Schmid, Christoph U. Keller, A. Boccaletti, J. L. Beuzit, Niranjan Thatte, R. G. Gratton, M. Kasper, Pierre Baudoz, Lars Venema, Christophe Verinaud, Florian Kerber, Natalia Yaitskova, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Pôle Astronomie du LESIA, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris
Subjects: Physics, Conceptual design, Planet, Astrophysics::Instrumentation and Methods for Astrophysics, Astrophysics::Solar and Stellar Astrophysics, Terrestrial planet, Astronomy, Direct imaging, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics::Galaxy Astrophysics, Exoplanet, Remote sensing
Abstract: Very soon, dedicated instruments developments at large telescopes (SPHERE for the VLT, GPI for Gemini) are about to discover and explore self-luminous giant planets by direct imaging and spectroscopy in significant numbers. The next generation of 30m-40m ground-based telescopes, the Extremely Large Telescopes (ELTs), have the potential to dramatically enlarge the discovery space towards older giant planets seen in reflected light and ultimately even a small number of rocky planets. EPICS is a proposed instrument for the European ELT, dedicated to the detection and characterization of expolanets by direct imaging and spectroscopy. EPICS is currently mid-way through a phase-A study carried out by a large European consortium which - by simulations and demonstration experiments - will investigate state-of-the-art diffraction and speckle suppression techniques to deliver highest contrasts. The final result of the study early 2010 will be a conceptual design and a development plan for the instrument. We will present the EPICS concept including the performance analysis and first results from prototyping experiments and discuss the main challenges and science capabilities of EPICS.
Published: 2016

40. Azimuthal asymmetries in the debris disk around HD61005 A massive collision of planetesimals?

Author: Anne-Marie Lagrange, Markus Janson, C. Thalmann, Dino Mesa, Johan Olofsson, D. Rouan, Th. Henning, R. G. Gratton, Andreas Bazzon, Graeme Salter, J. L. Beuzit, Carsten Dominik, Claudio Caceres, Christophe Pinte, Henning Avenhaus, Matthias R. Schreiber, Sascha P. Quanz, Amelia Bayo, J. Lannier, M. Feldt, Simon Casassus, Maud Langlois, Julien Milli, Gael Chauvin, Esther Buenzli, Anthony Boccaletti, Anne-Lise Maire, Hector Canovas, Arthur Vigan, J. C. Augereau, Matthias Samland, Attila Moór, Silvano Desidera, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Laboratoire Franco-Chilien d'Astronomie (LFCA), Universidad de Concepción [Chile]-Pontificia Universidad Católica de Chile (UC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Universidad de Chile, Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Low Energy Astrophysics (API, FNWI), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Universidad de Chile = University of Chile [Santiago] (UCHILE)-Pontificia Universidad Católica de Chile (UC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Universidad de Concepción - University of Concepcion [Chile]
Subjects: Physics, Debris disk, Planetesimal, 010308 nuclear & particles physics, media_common.quotation_subject, Astronomy and Astrophysics, Context (language use), Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, 01 natural sciences, Debris, 13. Climate action, Space and Planetary Science, Planet, 0103 physical sciences, Spectral energy distribution, Terrestrial planet, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Eccentricity (behavior), [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, media_common
Abstract: Context. Debris disks offer valuable insights into the latest stages of circumstellar disk evolution, and can possibly help us to trace the outcomes of planetary formation processes. In the age range 10 to 100 Myr, most of the gas is expected to have been removed from the system, giant planets (if any) must have already been formed, and the formation of terrestrial planets may be on-going. Pluto-sized planetesimals, and their debris released in a collisional cascade, are under their mutual gravitational influence, which may result into non-axisymmetric structures in the debris disk. Aims: High angular resolution observations are required to investigate these effects and constrain the dynamical evolution of debris disks. Furthermore, multi-wavelength observations can provide information about the dust dynamics by probing different grain sizes. Methods: Here we present new VLT/SPHERE and ALMA observations of the debris disk around the 40 Myr-old solar-type star HD 61005. We resolve the disk at unprecedented resolution both in the near-infrared (in scattered and polarized light) and at millimeter wavelengths. We perform a detailed modeling of these observations, including the spectral energy distribution. Results: Thanks to the new observations, we propose a solution for both the radial and azimuthal distribution of the dust grains in the debris disk. We find that the disk has a moderate eccentricity (e ~ 0.1) and that the dust density is two times larger at the pericenter compared to the apocenter. Conclusions: With no giant planets detected in our observations, we investigate alternative explanations besides planet-disk interactions to interpret the inferred disk morphology. We postulate that the morphology of the disk could be the consequence of a massive collision between ~1000 km-sized bodies at ~61 au. If this interpretation holds, it would put stringent constraints on the formation of massive planetesimals at large distances from the star. Based on observations made with ESO Telescopes at the Paranal Observatory under programs ID 095.C-0298 and 095.C-0273. Based on Herschel observations, OBSIDs: 1342270977, 1342270978, 1342270979, 1342270989, and 1342255147. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.The reduced images as FITS files, and data of Fig. 1 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/591/A108
Published: 2016

41. The GAPS Programme with HARPS-N@TNG XII: Characterization of the planetary system around HD108874

Author: P. Giacobbe, Silvano Desidera, E. Covino, Giuseppina Micela, A. Bignamini, Roberto Silvotti, K. Biazzo, Mario Damasso, A. S. Bonomo, A. Maggio, Cristina Knapic, Francesco Marzari, S. Masiero, Gloria Andreuzzi, M. Rainer, M. Pedani, S. Messina, G. Scandariato, I. Pagano, A. F. Martinez Fiorenzano, L. Di Fabrizio, Riccardo Smareglia, A. F. Lanza, V. Nascimbeni, Alessandro Sozzetti, Rosario Cosentino, C. Boccato, E. Poretti, Elisa Molinari, Ararat Harutyunyan, Riccardo Claudi, M. Esposito, S. Benatti, R. G. Gratton, Francesco Borsa, L. Malavolta, Laura Affer, G. Piotto, J. Maldonado, and ITA
Subjects: Rotation period, Physics, Stars: activity, Earth and Planetary Astrophysics (astro-ph.EP), Outer planets, 010308 nuclear & particles physics, Giant planet, Exomoon, Planetary systems, Stars: individual: HD 108874, Techniques: radial velocities, Astronomy and Astrophysics, Space and Planetary Science, Astronomy, FOS: Physical sciences, Planetary system, 01 natural sciences, Radial velocity, Planet, 0103 physical sciences, Astrophysics::Earth and Planetary Astrophysics, 010303 astronomy & astrophysics, Circumstellar habitable zone, Astrophysics - Earth and Planetary Astrophysics
Abstract: In order to understand the observed physical and orbital diversity of extrasolar planetary systems, a full investigation of these objects and of their host stars is necessary. Within this field, one of the main purposes of the GAPS observing project with HARPS-N@TNG is to provide a more detailed characterisation of already known systems. In this framework we monitored the star, hosting two giant planets, HD108874, with HARPS-N for three years in order to refine the orbits, to improve the dynamical study and to search for additional low-mass planets in close orbits. We subtracted the radial velocity (RV) signal due to the known outer planets, finding a clear modulation of 40.2 d period. We analysed the correlation between RV residuals and the activity indicators and modelled the magnetic activity with a dedicated code. Our analysis suggests that the 40.2 d periodicity is a signature of the rotation period of the star. A refined orbital solution is provided, revealing that the system is close to a mean motion resonance of about 9:2, in a stable configuration over 1 Gyr. Stable orbits for low-mass planets are limited to regions very close to the star or far from it. Our data exclude super-Earths with Msin i \gtrsim 5 M_Earth within 0.4 AU and objects with Msin i \gtrsim 2 M_Earth with orbital periods of a few days. Finally we put constraints on the habitable zone of the system, assuming the presence of an exomoon orbiting the inner giant planet., Comment: 10 pages; 11 figures; A&A Accepted
Published: 2016
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42. Resolving faint structures in the debris disk around TWA 7

Author: Francois Menard, Maud Langlois, Markus Janson, R. G. van Holstein, R. G. Gratton, Philippe Feautrier, Claudio Caceres, Wolfgang Brandner, D. Mawet, Graeme Salter, Th. Henning, E. Sissa, Amelia Bayo, Dino Mesa, M. Feldt, A. Roux, A. Pavlov, C. A. Grady, Gael Chauvin, Silvano Desidera, C. Perrot, David Mouillet, J. Lannier, Ch. Ginski, Philippe Thébault, Johan Olofsson, Thibaut Moulin, A-L. Maire, D. Le Mignant, A-M. Lagrange, T. Schmidt, Matthias R. Schreiber, C. Lazzoni, R. Ligi, Julien Milli, N. Godoy, C. Thalmann, Stephen Durkan, P. Rabou, Janis Hagelberg, Christophe Pinte, Quentin Kral, Anthony Boccaletti, L. Abe, Esther Buenzli, N. Engler, Hector Canovas, Arthur Vigan, Gérard Rousset, J. C. Augereau, Joshua E. Schlieder, S. Peretti, Ruben Asensio-Torres, and Mickael Bonnefoy
Subjects: Physics, Debris disk, Spiral galaxy, 010504 meteorology & atmospheric sciences, instrumentation: polarimeters, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Position angle, circumstellar matter, 01 natural sciences, Stars, instrumentation: high angular resolution, Space and Planetary Science, Planet, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Spectral energy distribution, Astrophysics::Earth and Planetary Astrophysics, Low Mass, 010303 astronomy & astrophysics, Planetary mass, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences
Abstract: Context. Debris disks are the intrinsic by-products of the star and planet formation processes. Most likely due to instrumental limitations and their natural faintness, little is known about debris disks around low mass stars, especially when it comes to spatially resolved observations. Aims. We present new VLT/SPHERE IRDIS dual-polarization imaging (DPI) observations in which we detect the dust ring around the M2 spectral type star TWA 7. Combined with additional angular differential imaging observations we aim at a fine characterization of the debris disk and setting constraints on the presence of low-mass planets. Methods. We modeled the SPHERE DPI observations and constrain the location of the small dust grains, as well as the spectral energy distribution of the debris disk, using the results inferred from the observations, and performed simple N-body simulations. Results. We find that the dust density distribution peaks at ~0.72′′ (25 au), with a very shallow outer power-law slope, and that the disk has an inclination of ~13° with a position angle of ~91° east of north. We also report low signal-to-noise ratio detections of an outer belt at a distance of ~1.5′′ (~52 au) from the star, of a spiral arm in the southern side of the star, and of a possible dusty clump at 0.11′′. These findings seem to persist over timescales of at least a year. Using the intensity images, we do not detect any planets in the close vicinity of the star, but the sensitivity reaches Jovian planet mass upper limits. We find that the SED is best reproduced with an inner disk at ~0.2′′ (~7 au) and another belt at 0.72′′ (25 au). Conclusions. We report the detections of several unexpected features in the disk around TWA 7. A yet undetected 100M⊕ planet with a semi-major axis at 20−30 au could possibly explain the outer belt as well as the spiral arm. We conclude that stellar winds are unlikely to be responsible for the spiral arm.
Published: 2018

43. Clues on the frequency of giant planets in wide orbits

Author: Mariangela Bonavita, C. Mordasini, J. Alibert, R. G. Gratton, Willy Benz, and Silvano Desidera
Subjects: Orbital elements, Physics, Semi-major axis, Monte Carlo method, Null (mathematics), General Engineering, Astronomy, Astronomy and Astrophysics, Direct imaging, Astrophysics, Stars, Space and Planetary Science, Planet, Astrophysics::Earth and Planetary Astrophysics
Abstract: The available results of deep imaging searches for planetary companions around nearby stars provide us useful constraints on the frequencies of giant planets in very wide orbits. Here we present some preliminary results of the Monte Carlo simulation which compare the published detection limits with the generated planetary masses and orbital parameters. This allow us to consider the impications of the null detection, which comes from the direct imaging techniques, on the distributions of mass and semimajor axis derived from the results of the other search techniques and also to check the agreement of the observations with the available planetary formation models.
Published: 2010

44. Line bisector analysis of stars with companions in the SARG survey at the TNG

Author: A. F. Martinez Fiorenzano, Silvano Desidera, Michael Endl, Rosario Cosentino, R. G. Gratton, and Massimo Cecconi
Subjects: Physics, General Engineering, Astronomy, Astronomy and Astrophysics, Astrophysics, Astronomical spectroscopy, Spectral line, Radial velocity, Stars, Space and Planetary Science, Planet, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Adaptive optics, Spectrograph, Line (formation)
Abstract: We present an analysis of how bisectors of spectral lines vary, for a few stars observed during the high-accuracy radial-velocity planet survey ongoing at the Telescopio Nazionale Galileo (TNG) using the Galileo High Resolution Spectrograph (Spettrografo Alta Risoluzione Galileo, SARG), and discuss their relation with differential radial velocities. The iodine cell lines employed in the radial velocity measurements were used to improve the wavelength calibration and then removed before bisector analysis. The line bisectors were then computed from average absorption profiles obtained by cross-correlation of the stellar spectra with a mask made from suitable lines of a solar catalog. Bisector velocity spans were determined and the run of bisector velocity span against radial velocity was studied to search for correlations between line asymmetries and radial velocity variations. We present an analysis of spectra of HD 216122B that show a slight contamination likely to be due to a stellar companion, and an analysis of spectra of HD 76036A, a case where the line bisectors are useful for improving the RV measurements. These systems are part of a survey sample being observed with adaptive optics (AdOpt at the TNG since 2006) in an attempt to visually resolve stellar companions.
Published: 2010

45. On the frequency of planets in multiple systems: an update

Author: Mariangela Bonavita, Silvano Desidera, and R. G. Gratton
Subjects: Physics, education.field_of_study, Space and Planetary Science, Planet, Population, General Engineering, Astronomy and Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics, education, Galaxy, Exoplanet
Abstract: The frequency of planets in binaries is an important issue in the field of extrasolar planet studies, because of its relevance in the estimate of the global planet population of our Galaxy and the clues it can give to our understanding of planet formation and evolution. Here we present an update of the results discussed in Bonavita & Desidera (2007) (hereafter BD07), where we reported the outcomes of our literature search for binaries and multiple systems among the sample with uniform detectability (UD) defined by Fischer & Valenti (2005) (hereafter FV05).
Published: 2010

46. Beryllium and the formation of the Thick Disk and of the Halo

Author: Luca Pasquini, Daniele Galli, P. Bonifacio, Rodolfo Smiljanic, R. G. Gratton, and Sofia Randich
Subjects: Physics, chemistry.chemical_element, Astronomy, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Dark matter halo, Galactic halo, chemistry, Thin disk, Space and Planetary Science, Thick disk, Galaxy formation and evolution, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Halo, Beryllium, Astrophysics::Galaxy Astrophysics, Galaxy rotation curve
Abstract: We use Beryllium to investigate star formation in the early Galaxy. Be has been demonstrated to be a good indicator of time in these early epochs. By analyzing the so-far largest sample of halo and thick disk metal poor stars, we find a clear scatter in Be for a given value of [Fe/H] and [O/H]. The scatter is very pronounced for Halo stars, while it is marginal for thick disk stars. Our halo stars separate in the [α/Fe] - Be diagram, showing two main branches: one indistinguishable from the thick disk stars, and one with lower [α/Fe] ratio. The stars belonging to this branch are characterized by highly eccentric orbits and small perigalactic radius (Rmin). Their kinematics are consistent with an accreted component.
Published: 2008

47. HD 17156 : a progress report

Author: Roi Alonso, Silvano Desidera, Riccardo Claudi, A. F. Martinez Fiorenzano, R. G. Gratton, Mauro Barbieri, Michael Endl, and Massimo Cecconi
Subjects: Physics, Space and Planetary Science, Astronomy, High resolution, Astronomy and Astrophysics, Astrophysics, Transit (astronomy), Planetary system
Abstract: We present an analysis of the HD planetary system based on a photometric transit dataset and radial velocities obtained on 3 December 2007. We also present limits on the presence of close stellar companions based on high resolution images.
Published: 2008

48. Detection of Solar‐like Oscillations in the G5 Subgiant μ Her

Author: Alfio Bonanno, S. Benatti, Silvio Leccia, Silvano Desidera, Lucio Paternò, Riccardo Claudi, and R. G. Gratton
Subjects: Physics, Range (particle radiation), Subgiant, Spectral density, Astronomy and Astrophysics, Astrophysics, law.invention, Power (physics), Telescope, Amplitude, Space and Planetary Science, law, Solar-like oscillations, Spectrograph
Abstract: A clear detection of excess of power, providing a substantial evidence for solar-like oscillations in the G5 subgiant \muher{}, is presented. This star was observed over seven nights with the SARG echelle spectrograph operating with the 3.6-m Italian TNG Telescope, using an iodine absorption cell as a velocity reference. A clear excess of power centered at 1.2 mHz, with peak amplitudes of about 0.9 \ms in the amplitude spectrum is present. Fitting the asymptotic relation to the power spectrum, a mode identification for the $\ell=0,1,2,3$ modes in the frequency range $900-1600 \muHz$ is derived. The most likely value for the large separation turns out to be 56.5 \muHz, consistent with theoretical expectations. The mean amplitude per mode ($l=0,1$) at peak power results to be $0.63 \rm m s^{-1}$, almost three times larger than the solar one.
Published: 2008

49. A new search for planet transits in NGC 6791

Author: Yazan Momany, F. De Marchi, Mauro Barbieri, P. B. Stetson, Hans Bruntt, M. Montalto, G. Grundahl, Silvano Desidera, Ennio Poretti, Riccardo Claudi, A. Arellano Ferro, Alfred Rosenberg, Giampaolo Piotto, Antonio Aparicio, and R. G. Gratton
Subjects: Physics, Metallicity, Astrophysics (astro-ph), FOS: Physical sciences, Astronomy and Astrophysics, Context (language use), Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, law.invention, Telescope, Stars, Star cluster, Space and Planetary Science, law, Planet, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Transit (astronomy), Astrophysics::Galaxy Astrophysics, Open cluster
Abstract: Context. Searching for planets in open clusters allows us to study the effects of dynamical environment on planet formation and evolution. Aims. Considering the strong dependence of planet frequency on stellar metallicity, we studied the metal rich old open cluster NGC 6791 and searched for close-in planets using the transit technique. Methods. A ten-night observational campaign was performed using the Canada-France-Hawaii Telescope (3.6m), the San Pedro M\'artir telescope (2.1m), and the Loiano telescope (1.5m). To increase the transit detection probability we also made use of the Bruntt et al. (2003) eight-nights observational campaign. Adequate photometric precision for the detection of planetary transits was achieved. Results. Should the frequency and properties of close-in planets in NGC 6791 be similar to those orbiting field stars of similar metallicity, then detailed simulations foresee the presence of 2-3 transiting planets. Instead, we do not confirm the transit candidates proposed by Bruntt et al. (2003). The probability that the null detection is simply due to chance coincidence is estimated to be 3%-10%, depending on the metallicity assumed for the cluster. Conclusions. Possible explanations of the null-detection of transits include: (i) a lower frequency of close-in planets in star clusters; (ii) a smaller planetary radius for planets orbiting super metal rich stars; or (iii) limitations in the basic assumptions. More extensive photometry with 3-4m class telescopes is required to allow conclusive inferences about the frequency of planets in NGC 6791., Comment: 23 pages, 23 figures, A&A accepted
Published: 2007

50. Na-O anticorrelation and horizontal branches

Author: Yazan Momany, Angela Bragaglia, Sara Lucatello, R. G. Gratton, and Eugenio Carretta
Subjects: Physics, education.field_of_study, Metallicity, Population, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Horizontal branch, Giant star, Stars, Star cluster, Space and Planetary Science, Globular cluster, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, education, Astrophysics::Galaxy Astrophysics, Galaxy cluster
Abstract: We are studying the Na-O anticorrelation in several globular clusters of different Horizontal Branch (HB) morphology in order to derive a possible relation between (primordial) chemical inhomogeneities and morphological parameters of the cluster population. We used the multifiber spectrograph FLAMES on the ESO Very Large Telescope UT2 and derived atmospheric parameters and elemental abundances of Fe, O and Na for about 150 red giant stars in the Galactic globular cluster NGC 6752. The average metallicity we derive is [Fe/H] = -1.56, in agreement with other results from red giants, but lower than obtained for dwarfs or early subgiants. In NGC 6752 there is not much space for an intrinsic spread in metallicity: on average, the rms scatter in [Fe/H] is 0.037 ± 0.003 dex, while the scatter expected on the basis of the major error sources is 0.039 ± 0.003 dex. The distribution of stars along the Na-O anticorrelation is different to what was found in the first paper of this series for the globular cluster NGC 2808: in NGC 6752 it is skewed toward more Na-poor stars, and it resembles more the one in M 13. Detailed modeling is required to clarify whether this difference may explain the very different distributions of stars along the HB.
Published: 2007

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