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1. 6 SCUTI STAR GX PEGASI: ADDITIONAL ANALYSIS

Author: S. V. Repin, E. Michel, M. Auvergne, A. Baglin, M. J. Goupil, L. S. Gurin, and Yu. O. Samoilova
Subjects: Astronomy, QB1-991
Abstract: Three criteria of the periodicity are discussed in the paper and their properties are investigated. These criteria are applied to investigate the periodicity properties of a variable star GX Pegasi. A number of periodic components are extracted.
Published: 2017
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2. The secondary eclipse of CoRoT-1b

Author: Roi Alonso, A. Léger, Tsevi Mazeh, François Bouchy, Laurent Jorda, Günther Wuchterl, Frederic Pont, Anders Erikson, Pierre Magain, Suzanne Aigrain, M. Pätzold, Magali Deleuil, Marc Ollivier, R. de la Reza, A. P. Hatzes, M. Fridlund, Antoine Llebaria, S. Chaintreuil, Hans J. Deeg, P. Gondoin, M. Barbieri, Pierre Barge, Helmut Lammer, A. Alapini, C. Moutou, Didier Queloz, Aldo S. Bonomo, M. Auvergne, Pascal Bordé, Jean Schneider, Heike Rauer, Tristan Guillot, D. Rouan, F. Fialho, A. Baglin, Rudolf Dvorak, Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), Université Nice Sophia Antipolis (... - 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 Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010504 meteorology & atmospheric sciences, photometry, media_common.quotation_subject, Flux, FOS: Physical sciences, Astrophysics, 01 natural sciences, 7. Clean energy, symbols.namesake, Bond albedo, Planet, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Black-body radiation, Circular orbit, Eccentricity (behavior), 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, media_common, Eclipse, Physics, Thermal equilibrium, Earth and Planetary Astrophysics (astro-ph.EP), Astronomy and Astrophysics, CoRoT, secondary eclipse, exoplanets, 13. Climate action, Space and Planetary Science, transit method, symbols, CoRoT-1b, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract: The transiting planet CoRoT-1b is thought to belong to the pM-class of planets, in which the thermal emission dominates in the optical wavelengths. We present a detection of its secondary eclipse in the CoRoT white channel data, whose response function goes from ~400 to ~1000 nm. We used two different filtering approaches, and several methods to evaluate the significance of a detection of the secondary eclipse. We detect a secondary eclipse centered within 20 min at the expected times for a circular orbit, with a depth of 0.016+/-0.006%. The center of the eclipse is translated in a 1-sigma upper limit to the planet's eccentricity of ecosomega, 6 pages, to appear in A&A, submitted 18 march 2009, accepted 7 July 2009
Published: 2016
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3. Planetary transit candidates in the CoRoT initial run: resolving their nature

Author: Eike W. Guenther, Günther Wuchterl, François Bouchy, Tsevi Mazeh, Magali Deleuil, S. Carpano, Francesco Pepe, C. Lovis, Martin Pätzold, Davide Gandolfi, J. M. Almenara, Suzanne Aigrain, Pierre Barge, Daniel Rouan, A. P. Hatzes, M. Fridlund, Laurent Jorda, C. Moutou, Antoine Llebaria, Michel Mayor, M. Auvergne, Pascal Bordé, Willy Benz, Jean Schneider, Heike Rauer, Marc Ollivier, Hans J. Deeg, G. Hebrard, Frederic Pont, M. Barbieri, A. Léger, Markus Rabus, P. Gondoin, R. de la Reza, Didier Queloz, B. Loeillet, Helmut Lammer, Petr Kabath, H. Bruntt, Tristan Guillot, Avi Shporer, A. Baglin, Rudolf Dvorak, Michaël Gillon, Anders Erikson, Pierre Magain, Roi Alonso, Stéphane Udry, Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), Université Nice Sophia Antipolis (... - 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 Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, photometry, 010308 nuclear & particles physics, Giant planet, Astronomy, Astronomy and Astrophysics, Astrophysics, Planetary system, Light curve, follow-up observations, 01 natural sciences, CoRoT, Radial velocity, Stars, exoplanets, transit method, Space and Planetary Science, Planet, 0103 physical sciences, Binary star, transit candidates, Transit (astronomy), 010303 astronomy & astrophysics
Abstract: With the release of CoRoT lightcurves of the Initial Run IRa01, 50 transiting planetary candidates have been published in a companion paper. About twenty of them were identified as binary stars from the CoRoT lightcurve itself. Complementary observations were conducted for 29 candidates, including ground-based photometry and radial-velocity measurements. Two giant planets were identified and fully characterized. Nineteen binaries are recognized, from which 10 are background eclipsing binaries in the CoRoT mask or triple systems, diluted by the main CoRoT target. Eight cases remain of unclear origin, one of them still being a planetary candidate. Comparison with simulations shows that the actual threshold of confirmed planet detection in this field does not yet fulfill the expectations, and a number of reasons are invoked, like the ranking process based on lightcurve analyses, and the strategy and limits of follow-up observations for targets fainter than magnitude 15.
Published: 2016
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4. Search for sub-kilometre trans-Neptunian objects using CoRoT asteroseismology data

Author: Hsiang-Kuang Chang, Chih-Yuan Liu, Franoise Roques, M. Auvergne, Alain Doressoundiram, Lucie Maquet, Observatoire de Paris, Université Paris sciences et lettres (PSL), 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), Departement de recherche SPAtiale (DESPA), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)
Subjects: Physics, [PHYS]Physics [physics], 010504 meteorology & atmospheric sciences, Astronomy, Astronomy and Astrophysics, 01 natural sciences, Asteroseismology, Space and Planetary Science, Asteroid, 0103 physical sciences, Trans-Neptunian object, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract: International audience
Published: 2015
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5. Low-amplitude rotational modulation rather than pulsations in the CoRoT B-type supergiant HD 46769

Author: Steven Bloemen, Pieter Degroote, C. Catala, R. Samadi, I. Papics, V. S. Schmid, R. Oestensen, Conny Aerts, Norberto Castro, E. Poretti, M. Auvergne, Sergio Simón-Díaz, M. Rainer, Coralie Neiner, Maryline Briquet, A. Baglin, F. Baudin, M. Scardia, E. Michel, Instituut voor Sterrenkunde [Leuven], Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Instituto de Astrofisica de Canarias (IAC), 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), INAF - Osservatorio Astronomico di Brera (OAB), Istituto Nazionale di Astrofisica (INAF), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), and Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES)
Subjects: Rotation period, Physics, [PHYS]Physics [physics], 010308 nuclear & particles physics, Phase dispersion minimization, Astronomy, FOS: Physical sciences, Astronomy and Astrophysics, Context (language use), Astrophysics, Type (model theory), Light curve, 01 natural sciences, Amplitude, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, 0103 physical sciences, ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, Polar, Astrophysics::Solar and Stellar Astrophysics, Supergiant, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), ComputingMilieux_MISCELLANEOUS
Abstract: {We aim to detect and interpret photometric and spectroscopic variability of the bright CoRoT B-type supergiant target HD\,46769 ($V=5.79$). We also attempt to detect a magnetic field in the target.} {We analyse a 23-day oversampled CoRoT light curve after detrending, as well as spectroscopic follow-up data, by using standard Fourier analysis and Phase Dispersion Minimization methods. We determine the fundamental parameters of the star, as well as its abundances from the most prominent spectral lines. We perform a Monte Carlo analysis of spectropolarimetric data to obtain an upper limit of the polar magnetic field, assumping a dipole field.} {In the CoRoT data, we detect a dominant period of 4.84\,d with an amplitude of 87\,ppm, and some of its (sub-)multiples. Given the shape of the phase-folded light curve and the absence of binary motion, we interpret the dominant variability in terms of rotational modulation, with a rotation period of 9.69\,d. Subtraction of the rotational modulation signal does not reveal any sign of pulsations. Our results are consistent with the absence of variability in the Hipparcos light curve. The spectroscopy leads to a projected rotational velocity of 72$\pm 2$\,km\,s$^{-1}$ and does not reveal periodic variability nor the need to invoke macroturbulent line broadening. No signature of a magnetic field is detected in our data. A field stronger than $\sim 500$\,G at the poles can be excluded, unless the possible non-detected field were more complex than dipolar.} {The absence of pulsations and of macroturbulence of this evolved B-type supergiant is placed into context of instability computations and of observed variability of evolved B-type stars.}, Comment: 9 pages, 4 tables, 8 figures, accepted for publication in A&A
Published: 2013
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6. Regular frequency patterns in the young δ Scuti star HD 261711 observed by the CoRoT and MOST satellites

Author: Slavek M. Rucinski, Dimitar Sasselov, David B. Guenther, A. F. J. Moffat, Luca Fossati, Werner W. Weiss, A. Baglin, M. Auvergne, K. Zwintz, N. Themessl, Rainer Kuschnig, J. M. Matthews, S. Chaintreuil, Jason F. Rowe, T. A. Ryabchikova, D. A. Bohlender, Thomas G. Barnes, Universität Insbruck, Space Research Institute of Austrian Academy of Sciences (IWF), Austrian Academy of Sciences (OeAW), Institute of Astronomy of the Russian Academy of Sciences (INASAN), Russian Academy of Sciences [Moscow] (RAS), 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), Natl Res Council Canada, Herzberg Inst Astrophys, Victoria, BC V9E 2E7 Canada, Natl Res Council Canada, Herzberg Inst Astrophys, Victoria, Institut für Astrophysik [Wien], Universität Wien, School of engineering sciences, University of Southampton, Department of Physics and Astronomy [Toronto], and York University [Toronto]
Subjects: Delta, Satellites, Techniques: spectroscopic, FOS: Physical sciences, Astrophysics, 01 natural sciences, Instability, Photometry, Photometry (optics), 0103 physical sciences, Spectroscopy, 010303 astronomy & astrophysics, Stars: oscillation, Solar and Stellar Astrophysics (astro-ph.SR), ComputingMilieux_MISCELLANEOUS, Physics, [PHYS]Physics [physics], 010308 nuclear & particles physics, Stars: individual, Astronomy and Astrophysics, Effective temperature, Light curve, Fourier series, Stars, Spectrum analysis, Radial velocity, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Stars: variables: delta scuti, Techniques: photometric, Open cluster
Abstract: We concentrate on an asteroseismological study of HD 261711, a rather hot delta Scuti type pulsating member of the young open cluster NGC 2264 located at the blue border of the instability region. HD 261711 was discovered to be a pre-main sequence delta Scuti star using the time series photometry obtained by the MOST satellite in 2006. High-precision, time-series photometry of HD 261711 was obtained by the MOST and CoRoT satellites in 4 separate new observing runs that are put into context with the star's fundamental atmospheric parameters obtained from spectroscopy. With the new MOST data set from 2011/12 and the two CoRoT light curves from 2008 and 2011/12, the delta Scuti variability was confirmed and regular groups of frequencies were discovered. The two pulsation frequencies identified in the data from the first MOST observing run in 2006 are confirmed and 23 new delta Scuti-type frequencies were discovered using the CoRoT data. Weighted average frequencies for each group are related to l=0 and l=1 p-modes. Evidence for amplitude modulation of the frequencies in two groups is seen. The effective temperature was derived to be 8600$\pm$200 K, log g is 4.1$\pm$0.2, and the projected rotational velocity is 53$\pm$1km/s. Using our Teff value and the radius of 1.8$\pm$0.5 Rsun derived from SED fitting, we get a log L/Lsun of 1.20$\pm$0.14 which agrees well to the seismologically determined values of 1.65 Rsun and, hence, a log L/Lsun of 1.13. The radial velocity of 14$\pm$2 km/s we derived for HD 261711, confirms the star's membership to NGC 2264. Our asteroseismic models suggest that HD 261711 is a delta Scuti-type star close to the zero-age main sequence (ZAMS) with a mass of 1.8 to 1.9Msun. HD 261711 is either a young ZAMS star or a late PMS star just before the onset of hydrogen-core burning., Comment: 12 pages, 13 figures, A&A accepted
Published: 2013
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7. Study of HD 169392A observed by CoRoT and HARPS

Author: M. Steslicki, Ian W. Roxburgh, Rasmus Handberg, M. Rainer, Yvonne Elsworth, L. Mantegazza, William J. Chaplin, Frédéric Baudin, A. Baglin, T. Roca Cortés, R. Samadi, S. Barceló Forteza, Clara Régulo, C. Catala, Graham A. Verner, S. Hekker, Rafael A. García, B. Mosser, E. Michel, Guy R. Davies, J. Ballot, Othman Benomar, E. Poretti, H. Bruntt, D. Salabert, M. Auvergne, S. Mathur, K. Uytterhoeven, Low Energy Astrophysics (API, FNWI), 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, 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: 010504 meteorology & atmospheric sciences, FOS: Physical sciences, Astrophysics, Double star, asteroseismology, 01 natural sciences, Asteroseismology, Measure (mathematics), Space exploration, 0103 physical sciences, 010303 astronomy & astrophysics, Stellar evolution, ComputingMilieux_MISCELLANEOUS, Solar and Stellar Astrophysics (astro-ph.SR), 0105 earth and related environmental sciences, Physics, Mode (statistics), Astronomy and Astrophysics, Radius, methods: data analysis, Stars, stars: individual: HD 169392, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, stars: oscillations, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: The numerous results obtained with asteroseismology thanks to space missions such as CoRoT and Kepler are providing a new insight on stellar evolution. After five years of observations, CoRoT is going on providing high-quality data. We present here the analysis of the double star HD169392 complemented by ground-based spectroscopic observations. This work aims at characterizing the fundamental parameters of the two stars, their chemical composition, the acoustic-mode global parameters including their individual frequencies, and their dynamics. We have analysed HARPS observations of the two stars to retrieve their chemical compositions. Several methods have been used and compared to measure the global properties of acoustic modes and their individual frequencies from the photometric data of CoRoT. The new spectroscopic observations and archival astrometric values suggest that HD169392 is a wide binary system weakly bounded. We have obtained the spectroscopic parameters for both components, suggesting the origin from the same cloud. However, only the mode signature of HD169392 A has been measured within the CoRoT data. The signal-to-noise ratio of the modes in HD169392B is too low to allow any confident detection. We were able to extract mode parameters of modes for l=0, 1, 2, and 3. The study of the splittings and inclination angle gives two possible solutions with splittings and inclination angles of 0.4-1.0 muHz and 20-40 degrees for one case and 0.2-0.5 muHz and 55-86 degrees for the other case. The modeling of this star with the Asteroseismic Modeling Portal led to a mass of 1.15+/-0.01 Ms, a radius of 1.88+/-0.02 Rs, and an age of 4.33+/-0.12 Gyr, where the uncertainties are the internal ones., Comment: 13 pages, 12 Figures, Accepted for publication in A&A
Published: 2013
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8. Transiting exoplanets from the CoRoT space mission. XXIII. CoRoT-21b: a doomed large Jupiter around a faint subgiant star

Author: J. Weingrill, M. Fridlund, Michael Endl, Hannu Parviainen, Pascal Bordé, A. Léger, François Bouchy, Sascha Grziwa, Brandon Tingley, Günther Wuchterl, Guillaume Hébrard, Sz. Csizmadia, Didier Queloz, A. S. Bonomo, Suzanne Aigrain, A. Llebaria, Tsevi Mazeh, A. P. Hatzes, Helmut Lammer, Alexandre Santerne, Annie Baglin, D. Rouan, Magali Deleuil, Rudolf Dvorak, Davide Gandolfi, J. M. Almenara, Tristan Guillot, Sylvio Ferraz-Mello, Ruben Diaz, William D. Cochran, Roi Alonso, Marc Ollivier, Juan Cabrera, Jean Schneider, C. Cavarroc, Ludmila Carone, Phillip J. MacQueen, Aviv Ofir, T. Pasternacki, Martin Pätzold, Michaël Gillon, Anders Erikson, M. Auvergne, Heike Rauer, Pierre Barge, C. Moutou, Hans J. Deeg, Laurent Jorda, 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, 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: 010504 meteorology & atmospheric sciences, planetary systems planet-star interactions extrasolar planets, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, 7. Clean energy, Jupiter, Rings of Jupiter, Planet, planet-star interactions, 0103 physical sciences, Hot Jupiter, MECÂNICA CELESTE, Astrophysics::Solar and Stellar Astrophysics, planetary systems, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Physics, Stellar rotation, Giant planet, Astronomy, Astronomy and Astrophysics, planetary systems – planet-star interactions, Exoplanet, 13. Climate action, Space and Planetary Science, ddc:520, Astrophysics::Earth and Planetary Astrophysics, Jupiter mass
Abstract: CoRoT-21, a F8IV star of magnitude V = 16 mag, was observed by the space telescope CoRoT during the Long Run 01 (LRa01) in the first winter field (constellation Monoceros) from October 2007 to March 2008. Transits were discovered during the light curve processing. Radial velocity follow-up observations, however, were performed mainly by the 10-m Keck telescope in January 2010. The companion CoRoT-21b is a Jupiter-like planet of 2.26 ± 0.33 Jupiter masses and 1.30 ± 0.14 Jupiter radii in an circular orbit of semi-major axis 0.0417 ± 0.0011 AU and an orbital period of 2.72474 ± 0.00014 days. The planetary bulk density is (1.36 ± 0.48) × 103 kg m-3, very similar to the bulk density of Jupiter, and follows an M1/3 − R relation like Jupiter. The F8IV star is a sub-giant star of 1.29 ± 0.09 solar masses and 1.95 ± 0.2 solar radii. The star and the planet exchange extremetidal forces that will lead to orbital decay and extreme spin-up of the stellar rotation within 800 Myr if the stellar dissipation is Q∗/k2∗ ≤ 107. CoRoT-21, a F8IV star of magnitude V = 16 mag, was observed by the space telescope CoRoT during the Long Run 01 (LRa01) in the first winter field (constellation Monoceros) from October 2007 to March 2008. Transits were discovered during the light curve processing. Radial velocity follow-up observations, however, were performed mainly by the 10-m Keck telescope in January 2010. The companion CoRoT-21b is a Jupiter-like planet of 2.26 ± 0.33 Jupiter masses and 1.30 ± 0.14 Jupiter radii in an circular orbit of semi-major axis 0.0417 ± 0.0011 AU and an orbital period of 2.72474 ± 0.00014 days. The planetary bulk density is (1.36 ± 0.48) × 103 kg m-3, very similar to the bulk density of Jupiter, and follows an M1/3 - R relation like Jupiter. The F8IV star is a sub-giant star of 1.29 ± 0.09 solar masses and 1.95 ± 0.2 solar radii. The star and the planet exchange extremetidal forces that will lead to orbital decay and extreme spin-up of the stellar rotation within 800 Myr if the stellar dissipation is Q∗/k2∗ ≤ 107. The CoRoT space mission, launched on December 27th 2006, has been developed and is operated by CNES, with the contribution of Austria, Belgium, Brazil, ESA (RSSD and Science Programme), Germany and Spain.
Published: 2012
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9. Pulsation spectrum of Delta Sct stars: the binary HD 50870 as seen with CoRoT and HARPS

Author: R. Garrido, E. Poretti, C. Catala, E. Michel, Pedro J. Amado, P. Mathias, A. Moya, A. García Hernández, M. Alvarez, R. Samadi, M. Auvergne, M. Rainer, L. Mantegazza, T. Semaan, J. C. Suárez, A. Baglin, F. Baudin, 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), Galaxies, Etoiles, Physique, Instrumentation (GEPI), and Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris
Subjects: Hertzsprung–Russell diagram, Binary number, FOS: Physical sciences, Angular velocity, Astrophysics, 01 natural sciences, symbols.namesake, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Binary system, Spectroscopy, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), ComputingMilieux_MISCELLANEOUS, Physics, [PHYS]Physics [physics], 010308 nuclear & particles physics, Spectral density, Astronomy and Astrophysics, Stars, Amplitude, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, symbols, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: We present the results obtained with the CoRoT satellite for HD 50870, a Delta Sct star which was observed for 114.4 d. The 307,570 CoRoT datapoints were analysed with different techniques. The photometric observations were complemented over 15 nights of high-resolution spectroscopy with HARPS on a baseline of 25 d. Some uvby photometric observations were also obtained to better characterize the pulsation modes. HD 50870 proved to be a low-amplitude, long-period spectroscopic binary system seen almost pole-on (i~21 deg. The brighter component, which also has the higher rotational velocity (v sin i=37.5 km/s), is a delta Sct-type variable. There is a dominant axisymmetric mode (17.16 c/d). After the detection of about 250 terms (corresponding to an amplitude of about 0.045 mmag) a flat plateau appears in the power spectrum in the low-frequency region up to about 35 c/d. We were able to detect this plateau only thanks to the short cadence sampling of the CoRoT measurements (32 s). The density distribution vs. frequency of the detected frequencies seems rule out the possibility that this plateau is the result of a process with a continuum power spectrum. The spacings of the strongest modes suggest a quasi-periodic pattern. We failed to find a satisfactory seismic model that simultaneously matches the frequency range, the position in the HR diagram, and the quasi-periodic pattern interpreted as a large separation. Nineteen modes were detected spectroscopically from the line profile variations and associated to the photometric ones. Tentative l,m values have been attributed to the modes detected spectroscopically. Prograde as well as retrograde modes are present with l degree values up to 9. There are no traces of variability induced by solar-like oscillations., 14 pages, 21 figures. Accepted for publication in A&A
Published: 2012
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10. Transiting exoplanets from the CoRoT space mission.XX.CoRoT-20b: A very high density, high eccentricity transiting giant planet

Author: Davide Gandolfi, A. Santerne, M. Fridlund, Eike W. Guenther, Tsevi Mazeh, François Bouchy, M. Havel, C. Cavarroc, Hannu Parviainen, M. Deleuil, H. Bruntt, Stefania Carpano, G. Hebrard, Laurent Jorda, J. M. Almenara, A. Baglin, Adrián Rodríguez, H. J. Deeg, Rudolf Dvorak, J. Weingrill, Sylvio Ferraz-Mello, Suzanne Aigrain, A. P. Hatzes, Roi Alonso, A. Léger, Tristan Guillot, Pascal Bordé, J. Cabrera, Jean Schneider, Pierre Barge, Brandon Tingley, Günther Wuchterl, A. S. Bonomo, C. Moutou, M. Gillon, M. Auvergne, D. Rouan, D. Queloz, Helmut Lammer, Heike Rauer, Marc Ollivier, Anders Erikson, Lev Tal-Or, Sz. Csizmadia, Aviv Ofir, Cilia Damiani, 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, 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, 010504 meteorology & atmospheric sciences, media_common.quotation_subject, Angular velocity, Astrophysics, stars: planetary systems - stars: fundamental parameters - techniques: photometry - techniques: radial velocities - techniques: spectroscopy, 01 natural sciences, Planet, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Eccentricity (behavior), Spin (physics), 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, media_common, Physics, [PHYS]Physics [physics], Giant planet, Astronomy and Astrophysics, Radius, Orbital period, ESPECTROSCOPIA, 13. Climate action, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: We report the discovery by the CoRoT space mission of a new giant planet, CoRoT-20b. The planet has a mass of 4.24 +/- 0.23 MJ and a radius of 0.84 +/- 0.04 RJ. With a mean density of 8.87 +/- 1.10 g/cm^3, it is among the most compact planets known so far. Evolution models for the planet suggest a mass of heavy elements of the order of 800 ME if embedded in a central core, requiring a revision either of the planet formation models or of planet evolution and structure models. We note however that smaller amounts of heavy elements are expected from more realistic models in which they are mixed throughout the envelope. The planet orbits a G-type star with an orbital period of 9.24 days and an eccentricity of 0.56. The star's projected rotational velocity is vsini = 4.5 +/- 1.0 km/s, corresponding to a spin period of 11.5 +/- 3.1 days if its axis of rotation is perpendicular to the orbital plane. In the framework of Darwinian theories and neglecting stellar magnetic breaking, we calculate the tidal evolution of the system and show that CoRoT-20b is presently one of the very few Darwin-stable planets that is evolving towards a triple synchronous state with equality of the orbital, planetary and stellar spin periods.
Published: 2012
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11. Planetary transit candidates in the CoRoT-SRc01 field

Author: A. Erikson, A. Santerne, S. Renner, P. Barge, S. Aigrain, A. Alapini, J.-M. Almenara, R. Alonso, M. Auvergne, A. Baglin, W. Benz, A. S. Bonomo, P. Bordé, F. Bouchy, H. Bruntt, J. Cabrera, L. Carone, S. Carpano, Sz. Csizmadia, M. Deleuil, H. J. Deeg, R. F. Díaz, R. Dvorak, S. Ferraz-Mello, M. Fridlund, D. Gandolfi, J.-C. Gazzano, M. Gillon, E. W. Guenther, T. Guillot, A. Hatzes, G. Hébrard, L. Jorda, H. Lammer, A. Léger, A. Llebaria, M. Mayor, T. Mazeh, C. Moutou, M. Ollivier, A. Ofir, M. Pätzold, F. Pepe, F. Pont, D. Queloz, M. Rabus, H. Rauer, C. Régulo, D. Rouan, B. Samuel, J. Schneider, A. Shporer, B. Tingley, S. Udry, G. Wuchterl, 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), Alonso Sobrino, Roi, Bouchy, François, Gillon, Michael, Mayor, Michel, Pepe, Francesco Alfonso, Queloz, Didier, and Udry, Stéphane
Subjects: [PHYS]Physics [physics], radial velocities [Techniques], 010308 nuclear & particles physics, 520 Astronomy, eclipsing [Binaries], photometric [Techniques], Astronomy and Astrophysics, techniques: photometric – techniques: radial velocities – techniques: spectroscopic – planetary systems – binaries: eclipsing, 620 Engineering, ESTRELAS, 01 natural sciences, spectroscopic [Techniques], Planetary systems, 13. Climate action, Space and Planetary Science, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, ddc:520, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, ComputingMilieux_MISCELLANEOUS
Abstract: Context. CoRoT is a pioneering space mission whose primary goals are stellar seismology and extrasolar planets search. Its surveys of large stellar fields generate numerous planetary candidates whose lightcurves have transit-like features. An extensive analytical and observational follow-up effort is undertaken to classify these candidates.Aims. We present the list of planetary transit candidates from the CoRoT LRa01 star field in the Monoceros constellation toward the Galactic anti-center direction. The CoRoT observations of LRa01 lasted from 24 October 2007 to 3 March 2008.Methods. We acquired and analyzed 7470 chromatic and 3938 monochromatic lightcurves. Instrumental noise and stellar variability were treated with several filtering tools by different teams from the CoRoT community. Different transit search algorithms were applied to the lightcurves.Results. Fifty-one stars were classified as planetary transit candidates in LRa01. Thirty-seven (i.e., 73% of all candidates) are “good” planetary candidates based on photometric analysis only. Thirty-two (i.e., 87% of the “good” candidates) have been followed-up. At the time of writing twenty-two cases were solved and five planets were discovered: three transiting hot-Jupiters (CoRoT-5b, CoRoT-12b, and CoRoT-21b), the first terrestrial transiting planet (CoRoT-7b), and another planet in the same system (CoRoT-7c, detected by radial velocity survey only). Evidence of another non-transiting planet in the CoRoT-7 system, namely CoRoT-7d, was recently found as well. Context. The space mission CoRoT is devoted to the analysis of stellar variability and the photometric detection of extrasolar planets. Aims: We present the list of planetary transit candidates detected in the first short run observed by CoRoT that targeted SRc01, towards the Galactic center in the direction of Aquila, which lasted from April to May 2007. Methods: Among the acquired data, we analyzed those for 1269 sources in the chromatic bands and 5705 in the monochromatic band. Instrumental noise and the stellar variability were treated with several detrending tools, to which several transit-search algorithms were subsequently applied. Results: Fifty-one sources were classified as planetary transit candidates and 26 were followed up with ground-based observations. Until now, no planet has been detected in the CoRoT data from the SRc01 field. The CoRoT space mission, launched on December 27th 2006, has been developed and is operated by CNES, with contributions from Austria, Belgium, Brazil, ESA, Germany, and Spain. The CoRoT data are available to the community from the CoRoT archive: http://idoc-corot.ias.u-psud.frBased in part on observations made with the 1.93-m telescope at Observatoire de Haute Provence (CNRS), France (SOPHIE Program 08A.PNP.MOUT).Based in part on observations made with the ESO-3.60-m telescope at La Silla Observatory (ESO), Chile (HARPS Program ESO - 081.C-0388) and with the ESO-VLT telescope at Paranal Observatory (ESO), Chile (FLAMES Program ESO - 081.C-0413).
Published: 2012
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12. Planetary transit candidates in the CoRoT LRa01 field

Author: M. Hartmann, Sylvio Ferraz-Mello, Roi Alonso, Rodrigo F. Díaz, Stéphane Udry, Heike Rauer, Pascal Bordé, Ludmila Carone, William D. Cochran, Lev Tal-Or, Lisa Nortmann, Clara Régulo, Laurent Jorda, C. Lovis, A. Léger, Stefania Carpano, Francesco Pepe, P. Eigmueller, Markus Rabus, Sz. Csizmadia, A. S. Bonomo, Michael Endl, A. Baglin, H. Bruntt, J. Weingrill, J. M. Almenara, Hannu Parviainen, Sascha Grziwa, J. C. Gazzano, Davide Gandolfi, Aviv Ofir, Rudolf Dvorak, Martin Paetzold, Avi Shporer, P. Gondoin, C. Moutou, S. Dreizler, Michaël Gillon, Anders Erikson, Hans J. Deeg, Suzanne Aigrain, Magali Deleuil, A. P. Hatzes, Brandon Tingley, Jean Schneider, J. Cabrera, Pierre Barge, A. Alapini, B. Samuel, Jochen Eisloeffel, S. Renner, Helmut Lammer, A. Llebaria, Didier Queloz, Günther Wuchterl, Neale P. Gibson, M. Fridlund, Tristan Guillot, Frederic Pont, R. de la Reza, B. Stecklum, M. Auvergne, Alexandre Santerne, Marc Ollivier, G. Hebrard, Eike W. Guenther, François Bouchy, Tsevi Mazeh, Petr Kabath, D. Rouan, Michel Mayor, Phillip J. MacQueen, M. Havel, Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), Université Nice Sophia Antipolis (... - 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, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Bouchy, François, Gillon, Michael, Lovis, Christophe, Mayor, Michel, Pepe, Francesco Alfonso, Queloz, Didier, Udry, Stéphane, 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, 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: photometry, FOS: Physical sciences, Context (language use), 01 natural sciences, Asteroseismology, photometric [techniques], techniques: photometric - techniques: radial velocities - techniques: spectroscopic - stars: planetary systems - binaries: eclipsing, eclipsing [binaries], spectroscopic, photometric, eclipsing, radial velocities, planetary systems, Primary (astronomy), Planet, 0103 physical sciences, Transit (astronomy), 010306 general physics, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, [PHYS]Physics [physics], Earth and Planetary Astrophysics (astro-ph.EP), 010308 nuclear & particles physics, Astronomy, ESTRELAS BINÁRIAS, Astronomy and Astrophysics, radial velocities [techniques], Exoplanet, Radial velocity, CoRoT, Stars, exoplanets, Space and Planetary Science, transit method, ddc:520, spectroscopic [techniques], Geology, Astrophysics - Earth and Planetary Astrophysics
Abstract: Context: CoRoT is a pioneering space mission whose primary goals are stellar seismology and extrasolar planets search. Its surveys of large stellar fields generate numerous planetary candidates whose lightcurves have transit-like features. An extensive analytical and observational follow-up effort is undertaken to classify these candidates. Aims: The list of planetary transit candidates from the CoRoT LRa01 star field in the Monoceros constellation towards the Galactic anti-center is presented. The CoRoT observations of LRa01 lasted from 24 October 2007 to 3 March 2008. Methods: 7470 chromatic and 3938 monochromatic lightcurves were acquired and analysed. Instrumental noise and stellar variability were treated with several filtering tools by different teams from the CoRoT community. Different transit search algorithms were applied to the lightcurves. Results: Fifty-one stars were classified as planetary transit candidates in LRa01. Thirty-seven (i.e., 73 % of all candidates) are "good" planetary candidates based on photometric analysis only. Thirty-two (i.e., 87 % of the "good" candidates) have been followed-up. At the time of this writing twenty-two cases have been solved and five planets have been discovered: three transiting hot-Jupiters (CoRoT-5b, CoRoT-12b, and CoRoT-21b), the first terrestrial transiting planet (CoRoT-7b), and another planet in the same system (CoRoT-7c, detected by radial velocity survey only). Evidences of another non-transiting planet in the CoRoT-7 system, namely CoRoT-7d, have been recently found., Comment: 30 pages, 15 figures, accepted for publication in A&A, Section 14 "Catalogs and Data"
Published: 2012
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13. Transiting exoplanets from the CoRoT space mission. XVI. CoRoT-14b: an unusually dense very hot Jupiter

Author: Eike W. Guenther, Tsevi Mazeh, Günther Wuchterl, Michael Endl, François Bouchy, Laurent Jorda, Davide Gandolfi, Sz. Csizmadia, J. M. Almenara, A. P. Hatzes, J. Cabrera, M. Auvergne, Aviv Ofir, Heike Rauer, Brandon Tingley, Sylvio Ferraz-Mello, L. Carone, Anders Erikson, Roi Alonso, M. Pätzold, M. Fridlund, D. Rouan, C. Lovis, A. S. Bonomo, B. Samuel, A. Llebaria, H. J. Deeg, T. Guillot, M. Gillon, A. Léger, Phillip J. MacQueen, A. Shporer, Jean Schneider, Stefania Carpano, A. Baglin, Rudolf Dvorak, Pierre Barge, William D. Cochran, C. Moutou, Pascal Bordé, H. Bruntt, Francesco Pepe, Marc Ollivier, M. Deleuil, Suzanne Aigrain, G. Hebrard, D. Queloz, Helmut Lammer, J. C. Gazzano, Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), Université Nice Sophia Antipolis (... - 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 Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Earth and Planetary Astrophysics (astro-ph.EP), Physics, COROT, Hot Jupiters, FOS: Physical sciences, Astronomy, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Space (mathematics), 01 natural sciences, Exoplanet, Jupiter, Orbit, Space and Planetary Science, Planet, extrasolar planets, 0103 physical sciences, Hot Jupiter, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, 010306 general physics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, ComputingMilieux_MISCELLANEOUS, Astrophysics - Earth and Planetary Astrophysics
Abstract: In this paper, the CoRoT Exoplanet Science Team announces its 14th discovery. Herein, we discuss the observations and analyses that allowed us to derive the parameters of this system: a hot Jupiter with a mass of $7.6 \pm 0.6$ Jupiter masses orbiting a solar-type star (F9V) with a period of only 1.5 d, less than 5 stellar radii from its parent star. It is unusual for such a massive planet to have such a small orbit: only one other known exoplanet with a higher mass orbits with a shorter period., 7 pages, 10 figures, accepted to Astronomy and Astrophysics
Published: 2011
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14. Non-radial oscillations in the red giant HR7349 measured by CoRoT

Author: T. Morel, Andrea Miglio, T. Kallinger, Josefina Montalbán, M. Auvergne, J. De Ridder, R. Samadi, S. Hekker, C. Catala, A. P. Hatzes, Caroline Barban, Fabien Carrier, E. Michel, Werner W. Weiss, A. Baglin, F. Baudin, Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, Institut d'astrophysique spatiale (IAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (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), Pôle Astronomie du LESIA, 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, Thüringer Landessternwarte, Tautenburg Observatory, School of Physics and Astronomy, University of Birmingham, Institut für Astronomie, Universität Wien (IfA), and Institut d'Astrophysique, Géophysique et Océanographie, Université de Liège
Subjects: Convection, Physics, Red giant, Spectral density, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Acoustic wave, Astrophysics::Cosmology and Extragalactic Astrophysics, Asteroseismology, Stars, Amplitude, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Speed of sound, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics
Abstract: Convection in red giant stars excites resonant acoustic waves whose frequencies depend on the sound speed inside the star, which in turn depends on the properties of the stellar interior. Therefore, asteroseismology is the most robust available method for probing the internal structure of red giant stars. Solar-like oscillations in the red giant HR7349 are investigated. Our study is based on a time series of 380760 photometric measurements spread over 5 months obtained with the CoRoT satellite. Mode parameters were estimated using maximum likelihood estimation of the power spectrum. The power spectrum of the high-precision time series clearly exhibits several identifiable peaks between 19 and 40 uHz showing regularity with a mean large and small spacing of Dnu = 3.47+-0.12 uHz and dnu_02 = 0.65+-0.10 uHz. Nineteen individual modes are identified with amplitudes in the range from 35 to 115 ppm. The mode damping time is estimated to be 14.7+4.7-2.9 days., 8 pages, A&A accepted
Published: 2010
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15. A transiting giant planet with a temperature between 250 K and 430 K

Author: Daniel Rouan, Günther Wuchterl, Pierre Barge, C. Lovis, Magali Deleuil, Frederic Pont, Sylvio Ferraz-Mello, François Bouchy, J. M. Almenara, David R. Ciardi, Roi Alonso, Jean Schneider, S. Carpano, Stéphane Udry, Sz. Csizmadia, Avi Shporer, T. A. Lister, G. Hebrard, Brandon Tingley, A. Baglin, Ludmila Carone, Rudolf Dvorak, Hans J. Deeg, A. P. Hatzes, P. Gondoin, M. Hidas, R. den Hartog, M. Havel, Petr Kabath, J. Weingrill, M. Fridlund, Laurent Jorda, H. Bruntt, Michaël Gillon, Anders Erikson, Willy Benz, Juan Cabrera, Eike W. Guenther, J.-C. Gazzano, Tsevi Mazeh, Marc Ollivier, Suzanne Aigrain, A. Léger, Markus Rabus, D. Queloz, Mauro Barbieri, Helmut Lammer, B. Stecklum, Tristan Guillot, Aldo S. Bonomo, A. Llebaria, Rachel Street, Michel Mayor, Heike Rauer, C. Moutou, Martin Pätzold, M. Auvergne, Francesco Pepe, Davide Gandolfi, Pascal Bordé, B. Samuel, Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), Université Nice Sophia Antipolis (... - 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 Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Multidisciplinary, 010504 meteorology & atmospheric sciences, Giant planet, Astronomy, Astrophysics, 01 natural sciences, Exoplanet, 13. Climate action, Planet, extrasolare Planeten - Transitmethode - CoRoT 9b, 0103 physical sciences, Terrestrial planet, Astrophysics::Solar and Stellar Astrophysics, Kepler-62, Astrophysics::Earth and Planetary Astrophysics, Primary atmosphere, 010303 astronomy & astrophysics, Planetary mass, 0105 earth and related environmental sciences, Discoveries of exoplanets
Abstract: Of the over 400 known1 exoplanets, there are about 70 planets that transit their central star, a situation that permits the derivation of their basic parameters and facilitates investigations of their atmospheres. Some short-period planets2, including the first terrestrial exoplanet3,4 (CoRoT-7b), have been discovered using a space mission5 designed to find smaller and more distant planets than can be seen from the ground. Here we report transit observations of CoRoT-9b, which orbits with a period of 95.274 days on a low eccentricity of 0.11 ± 0.04 around a solar-like star. Its periastron distance of 0.36 astronomical units is by far the largest of all transiting planets, yielding a ‘temperate’ photospheric temperature estimated to be between 250 and 430 K. Unlike previously known transiting planets, the present size of CoRoT-9b should not have been affected by tidal heat dissipation processes. Indeed, the planet is found to be well described by standard evolution models6 with an inferred interior composition consistent with that of Jupiter and Saturn.
Published: 2010
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16. The red-giant CoRoT target HR 7349

Author: Eric Michel, Claude Catala, Paolo Ventura, Thomas Kallinger, Werner W. Weiss, A. Baglin, F. Baudin, A. P. Hatzes, Fabien Carrier, Reza Samadi, Thierry Morel, Francesca D'Antona, Arlette Noels, P. Eggenberger, Ennio Poretti, Monica Rainer, Andrea Miglio, J. De Ridder, M. Auvergne, C. Barban, Josefina Montalbán, Saskia Hekker, Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, Institut d'Astrophysique, Géophysique et Océanographie, Université de Liège, 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, 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, Institut d'astrophysique spatiale (IAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), INAF-Osservatorio Astronomico di Roma (INAF-OAR), Observatoire Astronomique de l'Université de Genève, Thüringer Landessternwarte, Tautenburg Observatory, Institut für Astronomie, Universität Wien (IfA), and INAF-Osservatorio Astronomico di Brera (INAF-OAB)
Subjects: Physics, Red giant, K-type main-sequence star, Astronomy, Astronomy and Astrophysics, Astrophysics, Light curve, Cosmology, Photometry (optics), Stars, Space and Planetary Science, Solar-like oscillations, Parallax, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: International audience; HR 7349 is a bright [ V=5.8] red giant observed by CoRoT in the seismofield of the first long run. The outstanding CoRoT light curve allowed the detection of several solar-like oscillation modes (both radial and non-radial). On top of these seismic constraints, our observational knowledge on HR 7349 benefits as well from a precise parallax and detailed spectroscopic constraints. We present all the observational constraints that are available for the theoretical modelling of this most promising target.
Published: 2010
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17. Transiting exoplanets from the CoRoT space mission. X. CoRoT-10b: a giant planet in a 13.24 day eccentric orbit

Author: Pierre Barge, M. Pätzold, Marc Ollivier, M. Fridlund, A. P. Hatzes, François Bouchy, C. Moutou, J. Cabrera, Davide Gandolfi, A. F. Lanza, Willy Benz, A. S. Bonomo, Laurent Jorda, Pascal Bordé, D. Rouan, Sz. Csizmadia, Günther Wuchterl, M. Gillon, H. J. Deeg, A. Santerne, Sylvio Ferraz-Mello, Eike W. Guenther, Brandon Tingley, Roi Alonso, Tsevi Mazeh, Stéphane Udry, Stefania Carpano, A. Baglin, M. Havel, H. Bruntt, Rudolf Dvorak, Francesco Pepe, B. Samuel, M. Mayor, Jean Schneider, J. C. Gazzano, Antoine Llebaria, Anders Erikson, Suzanne Aigrain, A. Léger, Tristan Guillot, Andrew Collier Cameron, L. Carone, Heike Rauer, D. Queloz, Helmut Lammer, M. Auvergne, M. Deleuil, G. Hebrard, M. Barbieri, Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), Université Nice Sophia Antipolis (... - 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 Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010504 meteorology & atmospheric sciences, Extrasolare Planeten, Orbital eccentricity, Photometrie, Astrophysics::Cosmology and Extragalactic Astrophysics, 7. Clean energy, 01 natural sciences, Photometry (optics), Spitzer Space Telescope, Planet, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Physics, Giant planet, Astronomy, Astronomy and Astrophysics, Radialgeschwindigkeit, Exoplanet, Radial velocity, Stars, 13. Climate action, Space and Planetary Science, High Energy Physics::Experiment, Astrophysics::Earth and Planetary Astrophysics
Abstract: The space telescope CoRoT searches for transiting extrasolar planets by continuously monitoring the optical flux of thousands of stars in several fields of view. We report the discovery of CoRoT-10b, a giant planet on a highly eccentric orbit (e=0.53 +/- 0.04) revolving in 13.24 days around a faint (V=15.22) metal-rich K1V star. We use CoRoT photometry, radial velocity observations taken with the HARPS spectrograph, and UVES spectra of the parent star to derive the orbital, stellar and planetary parameters. We derive a radius of the planet of 0.97 +/- 0.07 R_Jup and a mass of 2.75 +/- 0.16 M_Jup. The bulk density, rho_pl=3.70 +/- 0.83 g/cm^3, is ~2.8 that of Jupiter. The core of CoRoT-10b could contain up to 240 M_Earth of heavy elements. Moving along its eccentric orbit, the planet experiences a 10.6-fold variation in insolation. Owing to the long circularisation time, tau_circ > 7 Gyr, a resonant perturber is not required to excite and maintain the high eccentricity of CoRoT-10b.
Published: 2010
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18. Frequency spacings of p-modes in red giants observed by CoRoT

Author: C. Barban, F. Baudin, B. Mosser, M.J. Goupil, J. De Ridder, R. Samadi, W.W. Weiss, M. Auvergne, A. Baglin, null the CoRoT Red Giant team, 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), Institut d'astrophysique spatiale (IAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, and Institut für Astronomie, Universität Wien (IfA)
Subjects: Physics, Turbulent convection, Stars, Space and Planetary Science, Excited state, Astrophysics::Solar and Stellar Astrophysics, Astronomy, Astronomy and Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics::Galaxy Astrophysics
Abstract: P-modes observed in red giants are acoustic resonances similar to those observed in the Sun, stochastically excited by turbulent convection. The high-quality and quasi-uninterrupted space data obtained by CoRoT allow us to make a big step forward in the study of such oscillations in red giants by increasing significantly the number of stars for which such oscillations can be detected. We present here the data analysis of a sample of red giants observed during the first long run of CoRoT (142 days). Detailed p-modes properties are estimated with a particular emphasis on the frequency spacings (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Published: 2010
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19. First CoRoT light curves of RR Lyrae stars. Complex multiplet structure and non-radial pulsation detections in V1127 Aquilae

Author: A. Baglin, Katrien Kolenberg, J. F. Le Borgne, Elisabeth Guggenberger, H. Trinquet, E. Poretti, M. Auvergne, J. M. Benko, Róbert Szabó, Werner W. Weiss, K. N. Grankin, Margit Paparo, Merieme Chadid, S. A. Artemenko, E. Chapellier, Giuseppe Bono, Jonas Debosscher, Laboratoire Hippolyte Fizeau (FIZEAU), 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), Konkoly Observatory, Research Center for Astronomy and Earth Sciences, Institut für Astronomie, Universität Wien (IfA), INAF-Osservatorio Astronomico di Brera (INAF-OAB), INAF-Osservatorio Astronomico di Roma (INAF-OAR), Laboratoire Astrophysique de Toulouse-Tarbes (LATT), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Scientific Research Institute Crimean Astrophysical Observatoryof the Ministries of Education and Sciences of Ukraine, 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, 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, and Instituut voor Sterrenkunde, Katholieke Universiteit Leuven
Subjects: Physics, Blazhko effect, Astronomy, Astronomy and Astrophysics, Context (language use), Astrophysics, RR Lyrae variable, Light curve, Stars, Amplitude, Settore FIS/05 - Astronomia e Astrofisica, Space and Planetary Science, Astrophysics::Solar and Stellar Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Phase modulation, Multiplet
Abstract: International audience; Context. The CoRoT - Convection Rotation and planetary Transits - space mission is a great opportunity for monitoring stars with excellent time-sampling and unprecedented photometric precision for up to 150 days. As an important benefit, high-quality RR Lyrae light curves are obtained with a quasi-uninterrupted coverage over several pulsation and Blazhko cycles. Aims: The Blazhko effect in RR Lyrae stars is an unsolved problem of astrophysics. We used the high-precision space data to contribute more precise knowledge to explain the possible physical processes behind the phenomenon. Methods: We applied different period-finding techniques including Period04, MuFrAn, PDM and SigSpec. Amplitude and phase modulation were investigated by an analytical function method as well as with the traditional O-C diagrams. Results: The Blazhko modulation frequency is directly detected in the spectrum, as well as its first and second harmonics. It shows the non-linear nature of the Blazhko modulation. Besides the triplets, further higher-order modulation side peaks appear around the pulsation frequency as quintuplet, septuplet, nonuplet, undecaplet, tredecaplet, quindecaplet and sepdecaplet structures. Additional frequencies, not belonging to the classical multiplet structures, are detected, as well as their linear combinations with the fundamental radial mode. We interpret these additional terms as non-radial modes. During the five consecutive Blazhko cycles, there is a shift of the maximum phase around 0.011 pulsation phase which is likely the consequence of a long term modulation.
Published: 2010
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20. Solar-like oscillations in a massive star

Author: Reza Samadi, Sébastien Deheuvels, Arlette Noels, Kevin Belkacem, Suzanne Talon, Thierry Appourchaux, Claude Catala, Marie-Jo Goupil, Eric Michel, Anne Thoul, Marc-Antoine Dupret, Josefina Montalbán, Richard Scuflaire, Laure Lefèvre, Andrea Miglio, M. Auvergne, A. Baglin, Frédéric Baudin, 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, 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, Ingénieurs, Techniciens et Administratifs, Institut d'Astrophysique, Géophysique et Océanographie, Université de Liège, Institut d'astrophysique spatiale (IAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), and Réseau Québécois de Calcul de Haute Performance, Université de Montréal (DGTIC)
Subjects: Physics, Convection, Multidisciplinary, Oscillation, FOS: Physical sciences, Astronomy, Astrophysics, Rotation, Asteroseismology, Stars, Astrophysics - Solar and Stellar Astrophysics, Physics::Space Physics, Astrophysics::Solar and Stellar Astrophysics, Solar-like oscillations, Baryon acoustic oscillations, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Solar and Stellar Astrophysics (astro-ph.SR), Main sequence
Abstract: Seismology of stars provides insight into the physical mechanisms taking place in their interior, with modes of oscillation probing different layers. Low-amplitude acoustic oscillations excited by turbulent convection were detected four decades ago in the Sun and more recently in low-mass main-sequence stars. Using data gathered by the Convection Rotation and Planetary Transits mission, we report here on the detection of solar-like oscillations in a massive star, V1449 Aql, which is a known large-amplitude (b Cephei) pulsator., Published in Sience, 19 June 2009, vol. 324, p. 1540
Published: 2009
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21. Noise properties of the CoRoT data: a planet-finding perspective

Author: P. Gondoin, Helmut Lammer, M. Auvergne, Anders Erikson, Heike Rauer, M. Fridlund, Shay Zucker, P. Guterman, D. Rouan, Pierre Magain, A. Alapini, Francois Fressin, Suzanne Aigrain, Roi Alonso, Laurent Jorda, Rudolf Dvorak, Didier Queloz, Marc Ollivier, Antoine Llebaria, M. Barbieri, G. Wuchter, Pascal Bordé, Martin Pätzold, R. de la Reza, François Bouchy, Jean Schneider, Tsevi Mazeh, Pierre Barge, A. Léger, C. Moutou, Hans J. Deeg, Frederic Pont, Magali Deleuil, University of Exeter, Harvard-Smithsonian Center for Astrophysics, 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), Institut d'astrophysique spatiale (IAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Observatoire de Haute-Provence (OHP), Institut Pythéas (OSU PYTHEAS), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Instituto de Astrofisica de Canarias (IAC), Observatório Nacional/MCTI, Institut für Astronomie, Universität Wien (IfA), DLR Institut für Planetenerkundung, Research and Scientific Support Department, ESA-ESTEC (RSSD), Institut für Weltraumforschung, Österreichische Akademie der Wissenschaften (IWF), University of Liège, Tel Aviv University (TAU), Rheinisches Institut für Umweltforschung an der Universität zu Köln (RIU), Observatoire Astronomique de l'Université de Genève, Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and Thüringer Landessternwarte, Tautenburg Observatory
Subjects: noise, photometry, Population, transit search, FOS: Physical sciences, Astrophysics, Filter (large eddy simulation), Planet, Astrophysics::Solar and Stellar Astrophysics, education, Instrumentation and Methods for Astrophysics (astro-ph.IM), Solar and Stellar Astrophysics (astro-ph.SR), Physics, Earth and Planetary Astrophysics (astro-ph.EP), education.field_of_study, Astronomy and Astrophysics, Planetary system, Light curve, CoRoT, Stars, Astrophysics - Solar and Stellar Astrophysics, exoplanets, Space and Planetary Science, transit method, Magnitude (astronomy), Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Noise (radio), Astrophysics - Earth and Planetary Astrophysics
Abstract: In this short paper, we study the photometric precision of stellar light curves obtained by the CoRoT satellite in its planet finding channel, with a particular emphasis on the timescales characteristic of planetary transits. Together with other articles in the same issue of this journal, it forms an attempt to provide the building blocks for a statistical interpretation of the CoRoT planet and eclipsing binary catch to date. After pre-processing the light curves so as to minimise long-term variations and outliers, we measure the scatter of the light curves in the first three CoRoT runs lasting more than 1 month, using an iterative non-linear filter to isolate signal on the timescales of interest. The bevhaiour of the noise on 2h timescales is well-described a power-law with index 0.25 in R-magnitude, ranging from 0.1mmag at R=11.5 to 1mmag at R=16, which is close to the pre-launch specification, though still a factor 2-3 above the photon noise due to residual jitter noise and hot pixel events. There is evidence for a slight degradation of the performance over time. We find clear evidence for enhanced variability on hours timescales (at the level of 0.5 mmag) in stars identified as likely giants from their R-magnitude and B-V colour, which represent approximately 60 and 20% of the observed population in the direction of Aquila and Monoceros respectively. On the other hand, median correlated noise levels over 2h for dwarf stars are extremely low, reaching 0.05mmag at the bright end., Comment: 5 pages, 4 figures, accepted for publication in A&A
Published: 2009
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22. The CoRoT satellite in flight : description and performance

Author: M. Auvergne, P. Bodin, L. Boisnard, J.-T. Buey, S. Chaintreuil, G. Epstein, M. Jouret, T. Lam-Trong, P. Levacher, A. Magnan, R. Perez, P. Plasson, J. Plesseria, G. Peter, M. Steller, D. Tiphène, A. Baglin, P. Agogué, T. Appourchaux, D. Barbet, T. Beaufort, R. Bellenger, R. Berlin, P. Bernardi, D. Blouin, P. Boumier, F. Bonneau, R. Briet, B. Butler, R. Cautain, F. Chiavassa, V. Costes, J. Cuvilho, V. Cunha-Parro, F. De Oliveira Fialho, M. Decaudin, J.-M. Defise, S. Djalal, A. Docclo, R. Drummond, O. Dupuis, G. Exil, C. Fauré, A. Gaboriaud, P. Gamet, P. Gavalda, E. Grolleau, L. Gueguen, V. Guivarc'h, P. Guterman, J. Hasiba, G. Huntzinger, H. Hustaix, C. Imbert, G. Jeanville, B. Johlander, L. Jorda, P. Journoud, F. Karioty, L. Kerjean, L. Lafond, V. Lapeyrere, P. Landiech, T. Larqué, P. Laudet, J. Le Merrer, L. Leporati, B. Leruyet, B. Levieuge, A. Llebaria, L. Martin, E. Mazy, J.-M. Mesnager, J.-P. Michel, J.-P. Moalic, W. Monjoin, D. Naudet, S. Neukirchner, K. Nguyen-Kim, M. Ollivier, J.-L. Orcesi, H. Ottacher, A. Oulali, J. Parisot, S. Perruchot, A. Piacentino, L. Pinheiro da Silva, J. Platzer, B. Pontet, A. Pradines, C. Quentin, U. Rohbeck, G. Rolland, F. Rollenhagen, R. Romagnan, N. Russ, R. Samadi, R. Schmidt, N. Schwartz, I. Sebbag, H. Smit, W. Sunter, M. Tello, P. Toulouse, B. Ulmer, O. Vandermarcq, E. Vergnault, R. Wallner, G. Waultier, P. Zanatta, 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), 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), 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: FOS: Physical sciences, Astrophysics, 7. Clean energy, 01 natural sciences, law.invention, Telescope, planetary systems -stars, Spitzer Space Telescope, law, 0103 physical sciences, Ground segment, photometers -stars, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), instrumentation, Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Spacecraft, 010308 nuclear & particles physics, Payload, business.industry, Astronomy and Astrophysics, Geodesy, Exoplanet, South Atlantic Anomaly, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, oscillations, Satellite, business
Abstract: CoRoT is a space telescope dedicated to stellar seismology and the search for extrasolar planets. The mission is led by CNES in association with French laboratories and has a large international participation: the European Space Agency (ESA), Austria, Belgium and Germany contribute to the payload, and Spain and Brazil contribute to the ground segment. Development of the spacecraft, which is based on a PROTEUS low earth orbit recurrent platform, commenced in October 2000 and the satellite was launched on December 27th 2006. The instrument and platform characteristics prior to launch have been described in ESA publication (SP-1306) . In the present paper we detail the behaviour in flight, based on raw and corrected data. Five runs have been completed since January 2007. The data used here are essentially those acquired during the commissioning phase and from a long run which lasted 146 days, these enable us to give a complete overview of the instrument and platform behaviour for all environmental conditions. The ground based data processing is not described in detail, the most important method being published elsewhere. It is shown that the performance specifications are easily satisfied when the environmental conditions are favourable. Most of the perturbations, and consequently data corrections, are related to Low Earth Orbit (LEO) perturbations: high energy particles inside the South Atlantic Anomaly (SAA), eclipses and temperature variations, and line of sight fluctuations due to the attitude control system. Straylight due to the reflected light from the earth, which is controlled by the telescope and baffle design, appears to be negligible., 14 pages ; 30 figures ; accepted for publication in A&A
Published: 2009
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23. Magnetic activity in the photosphere of CoRoT-Exo-2a Active longitudes and short-term spot cycle in a young Sun-like star

Author: S. Messina, Bernard Foing, Adriana V. R. Silva, J. R. De Medeiros, M. Comparato, M. Auvergne, Werner W. Weiss, Roi Alonso, A. Baglin, Pierre Barge, Suzanne Aigrain, Padmakar Parihar, C. Moutou, A. Collier Cameron, I. Pagano, Patrick Boumier, Giuseppe Cutispoto, Antonino F. Lanza, Andreas Kaiser, Giuseppe Leto, Aldo S. Bonomo, INAF-Osservatorio Astrofisico di Catania (INAF-OACt), University of Exeter, 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), Institut d'astrophysique spatiale (IAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), School of Physics and Astronomy, University of St Andrews, Departamento de Física, Universidade Federal do Rio Grande do Norte, ESA-ESTEC, Institut für Astronomie, Universität Wien (IfA), Indian Institute of Astrophysics, and Centro de Rádio Astronomia e Astrofísica Mackenzie (CRAAM)
Subjects: Physics, Rotation period, Photosphere, Astrophysics (astro-ph), magnetic fields [Stars], FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Light curve, Orbital period, Solar irradiance, rotation [Stars], individual: CoRoT-Exo-2a [Stars], Planetary systems, Space and Planetary Science, Planet, late-type [Stars], Hot Jupiter, Differential rotation, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], activity [Stars]
Abstract: The space experiment CoRoT has recently detected transits by a hot Jupiter across the disc of an active G7V star (CoRoT-Exo-2a) that can be considered as a good proxy for the Sun at an age of approximately 0.5 Gyr. We present a spot modelling of the optical variability of the star during 142 days of uninterrupted observations performed by CoRoT with unprecedented photometric precision. We apply spot modelling approaches previously tested in the case of the Sun by modelling total solar irradiance variations. To model the light curve of CoRoT-Exo-2a, we take into account both the photometric effects of cool spots as well as those of solar-like faculae, adopting solar analogy. Two active longitudes initially on opposite hemispheres are found on the photosphere of CoRoT-Exo-2a with a rotation period of 4.522 $\pm$ 0.024 days. Their separation changes by approximately 80 degrees during the time span of the observations. From this variation, a relative amplitude of the surface differential rotation lower than about 1 percent is estimated. Individual spots form within the active longitudes and show an angular velocity about 1 percent smaller than that of the longitude pattern. The total spotted area shows a cyclic oscillation with a period of 28.9 $\pm$ 4.3 days, which is close to 10 times the synodic period of the planet as seen by the rotating active longitudes. The implications of such results for the internal rotation of CoRoT-Exo-2a are discussed on the basis of solar analogy. A possible magnetic star-planet interaction is suggested by the cyclic variation of the spotted area. Alternatively, the 28.9-d cycle may be related to Rossby-type waves propagating in the subphotospheric layers of the star., Comment: 9 pages, 8 figures, accepted by Astronomy and Astrophysics
Published: 2009
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24. Photospheric activity and rotation of the planet-hosting star CoRoT-4a

Author: Pierre Barge, M. Deleuil, C. Moutou, G. Leto, Suzanne Aigrain, Giuseppe Cutispoto, A. F. Lanza, A. Collier Cameron, J. R. De Medeiros, S. Messina, A. Baglin, I. Pagano, M. Auvergne, A. S. Bonomo, Bernard Foing, INAF-Osservatorio Astrofisico di Catania (INAF-OACt), University of Exeter, 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), 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), School of Physics and Astronomy, University of St Andrews, Departamento de Física, Universidade Federal do Rio Grande do Norte, and ESA-ESTEC
Subjects: magnetic fields [Stars], FOS: Physical sciences, Astrophysics, Planet, Hot Jupiter, Differential rotation, Astrophysics::Solar and Stellar Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Earth and Planetary Astrophysics (astro-ph.EP), Physics, Sunspot, Stellar rotation, Astronomy and Astrophysics, Planetary system, Light curve, Orbital period, rotation [Stars], Planetary systems, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, late-type [Stars], Astrophysics::Earth and Planetary Astrophysics, individual: CoRoT-4a [Stars], [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], activity [Stars], Astrophysics - Earth and Planetary Astrophysics
Abstract: The space experiment CoRoT has recently detected a transiting hot Jupiter in orbit around a moderately active F-type main-sequence star (CoRoT-Exo-4a). This planetary system is of particular interest because it has an orbital period of 9.202 days, the second longest one among the transiting planets known to date. We study the surface rotation and the activity of the host star during an uninterrupted sequence of optical observations of 58 days. Our approach is based on a maximum entropy spot modelling technique extensively tested by modelling the variation of the total solar irradiance. It assumes that stellar active regions consist of cool spots and bright faculae, analogous to sunspots and solar photospheric faculae, whose visibility is modulated by stellar rotation. The modelling of the light curve of CoRoT-Exo-4a reveals three main active longitudes with lifetimes between about 30 and 60 days that rotate quasi-synchronously with the orbital motion of the planet. The different rotation rates of the active longitudes are interpreted in terms of surface differential rotation and a lower limit of 0.057 \pm 0.015 is derived for its relative amplitude. The enhancement of activity observed close to the subplanetary longitude suggests a magnetic star-planet interaction, although the short duration of the time series prevents us from drawing definite conclusions., 8 pages, 6 figures, accepted by Astronomy & Astrophysics
Published: 2009
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25. Evidence for nonlinear resonant mode coupling in the beta Cephei star HD 180642 (V1449 Aquilae) from CoRoT photometry

Author: Fabien Carrier, C. Catala, Maryline Briquet, A. Baglin, E. Michel, P. Degroote, K. Uytterhoeven, T. Morel, Karolien Lefever, Conny Aerts, M. Auvergne, Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, 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), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)
Subjects: Physics, oscillations [stars], 010308 nuclear & particles physics, time-series, Astronomy and Astrophysics, strange modes, Astrophysics, asteroseismology, Light curve, hipparcos, 01 natural sciences, Phase locking, Photometry (optics), Nonlinear system, pulsators, individual: hd 180642 (v1449 aql) [stars], Space and Planetary Science, variables: general [stars], pulsational frequency-analysis, 0103 physical sciences, Mode coupling, Time series, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics
Abstract: International audience; Context: We present the CoRoT light curve of the beta Cep star HD 180642, assembled during the first long run of the space mission, as well as archival single-band photometry. Aims: Our goal is to analyse the detailed behaviour present in the light curve and interpret it in terms of excited-mode frequencies. Methods: After describing the noise properties in detail, we use various time series analyses and fitting techniques to model the CoRoT light curve, for various physical assumptions. We apply statistical goodness-of-fit criteria that allow us to select the most appropriate physical model fit to the data. Results: We conclude that the light-curve model based on nonlinear resonant frequency and phase locking provides the best representation of the data. Interpretation of the residuals is dependent on the chosen physical model used to prewhiten the data. Conclusions: Our observational results constitute a fruitful starting point for detailed seismic stellar modelling of this large-amplitude and evolved beta Cep star.
Published: 2009
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26. Pulsations in the late-type Be star HD 50 209 detected by CoRoT

Author: C. Martayan, B. de Batz, C. Catala, C. Neiner, E. Poretti, R. Garrido, Juan Gutiérrez-Soto, Juan Fabregat, M. Rainer, F. Espinosa-Lara, M. Floquet, B. Leroy, A. L. Huat, E. Michel, P. D. Diago, Eduardo Janot-Pacheco, L. Andrade, R. Samadi, M. Auvergne, Yves Fremat, Marcelo Emilio, T. Semaan, Anne-Marie Hubert, J. Suso, K. Uytterhoeven, Universitat de València (UV), Galaxies, Etoiles, Physique, Instrumentation (GEPI), 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), Physique stellaire et galactique, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-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, Observatoire Royal de Belgique (ORB), Instituto de Astrofisica de Andalucia, CSIC (IAA), Departamento de Astronomia Instituto de Astronomia, Geofísica e Ciências Atmosféricas, Universidade de São Paulo, Obervatório Astronômico, Universidade Estadual de Ponta Grossa, and INAF-Osservatorio Astronomico di Brera (INAF-OAB)
Subjects: Rotation period, Be star, Hertzsprung–Russell diagram, FOS: Physical sciences, Astrophysics, Star (graph theory), 01 natural sciences, Spectral line, symbols.namesake, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Physics, 010308 nuclear & particles physics, Astronomy and Astrophysics, Light curve, Ciència Ensenyament, Stars, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Astronomia, symbols, Astrophysics::Earth and Planetary Astrophysics, Instability strip, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: The presence of pulsations in late-type Be stars is still a matter of controversy. It constitutes an important issue to establish the relationship between non-radial pulsations and the mass-loss mechanism in Be stars. To contribute to this discussion, we analyse the photometric time series of the B8IVe star HD 50209 observed by the CoRoT mission in the seismology field. We use standard Fourier techniques and linear and non-linear least squares fitting methods to analyse the CoRoT light curve. In addition, we applied detailed modelling of high-resolution spectra to obtain the fundamental physical parameters of the star. We have found four frequencies which correspond to gravity modes with azimuthal order m=0,-1,-2,-3 with the same pulsational frequency in the co-rotating frame. We also found a rotational period with a frequency of 0.679 \cd (7.754 $\mu$Hz). HD 50209 is a pulsating Be star as expected from its position in the HR diagram, close to the SPB instability strip., Comment: 7 pages, 8 figures, accepted fot publication in the A&A CoRoT special feature
Published: 2009
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27. HD 51106 and HD 50747: an ellipsoidal binary and a triple system observed with CoRoT

Author: J. C. Valtier, K. Uytterhoeven, N. Dolez, R. Samadi, C. Catala, A. Hui Bon Hua, P. Mathias, E. Poretti, G. Vauclair, M. Auvergne, E. Michel, M. Rainer, Pedro J. Amado, D. Le Contel, Sylvie Vauclair, A. Baglin, Laboratoire Astrophysique de Toulouse-Tarbes (LATT), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -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), Laboratoire Hippolyte Fizeau (FIZEAU), 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), INAF-Osservatorio Astronomico di Brera (INAF-OAB), Instituto de Astrofisica de Andalucia, CSIC (IAA), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: Physics, Oscillation, Triple system, FOS: Physical sciences, Binary number, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Star (graph theory), Light curve, Stars, symbols.namesake, Fourier transform, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, symbols, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Variable star, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics
Abstract: We present an analysis of the observations of HD 51106 and HD 50747 by the satellite CoRoT, obtained during its initial run, and of the spectroscopic preparatory observations. AIMS: We complete an analysis of the light curve, extract the main frequencies observed, and discuss some preliminary interpretations about the stars. Methods: We used standard Fourier transform and pre-whitening methods to extract information about the periodicities of the stars. Results: HD 51106 is an ellipsoidal binary, the light curve of which can be completely explained by the tidal deformation of the star and smaller secondary effects. HD 50747 is a triple system containing a variable star, which exhibits many modes of oscillation with periods in the range of a few hours. On the basis of this period range and the analysis of the physical parameters of the star, we conclude that HD 50747 is a Gamma-Doradus star., Comment: 7 pages, 8 figures, use (Astronomy-Astrophysics format/macro LAtex)
Published: 2009
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28. The B0.5IVe CoRoT target HD 49330. I. Photometric analysis from CoRoT data

Author: F. Baudin, Eduardo Janot-Pacheco, L. Andrade, Christophe Martayan, Y. Frémat, T. Semaan, Coralie Neiner, F. Espinosa Lara, Juan Fabregat, A. L. Huat, P. D. Diago, Anne-Marie Hubert, Eric Michel, Michele Floquet, B. Leroy, C. Catala, R. Samadi, M. Auvergne, B. de Batz, J. Suso, Marcelo Emilio, Juan Gutiérrez-Soto, Galaxies, Etoiles, Physique, Instrumentation (GEPI), 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), Physique stellaire et galactique, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Institut d'astrophysique spatiale (IAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Observatoire Royal de Belgique (ORB), Universidade de São Paulo, Universitat de València (UV), Obervatório Astronômico, Universidade Estadual de Ponta Grossa, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), and Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris
Subjects: Physics, Be star, Hertzsprung–Russell diagram, Astrophysics::High Energy Astrophysical Phenomena, Astronomy, Astronomy and Astrophysics, Context (language use), Astrophysics, Light curve, Stars, symbols.namesake, Amplitude, Space and Planetary Science, [SDU]Sciences of the Universe [physics], symbols, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Emission spectrum, Instability strip, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics::Galaxy Astrophysics
Abstract: International audience; Context: Be stars undergo outbursts producing a circumstellar disk from the ejected material. The beating of non-radial pulsations has been put forward as a possible mechanism of ejection. Aims: We analyze the pulsational behavior of the early B0.5IVe star HD 49330 observed during the first CoRoT long run towards the Galactical anticenter (LRA1). This Be star is located close to the lower edge of the beta Cephei instability strip in the HR diagram and showed a 0.03 mag outburst during the CoRoT observations. It is thus an ideal case for testing the aforementioned hypothesis. Methods: We analyze the CoRoT light curve of HD 49330 using Fourier methods and non-linear least square fitting. Results: In this star, we find pulsation modes typical of beta Cep stars (p modes) and SPB stars (g modes) with amplitude variations along the run directly correlated with the outburst. These results provide new clues about the origin of the Be phenomenon as well as strong constraints on the seismic modelling of Be stars.
Published: 2009
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29. The CoRoT-7 planetary system: two orbiting super-Earths

Author: François Bouchy, Marc Ollivier, Davide Gandolfi, Pierre Barge, S. Ferraz Mello, Jean Schneider, C. Moutou, M. Fridlund, Michaël Gillon, Anders Erikson, Eike W. Guenther, Pierre Magain, Roi Alonso, A. P. Hatzes, Guillaume Hébrard, Stéphane Udry, Tristan Guillot, A. Baglin, Rudolf Dvorak, Willy Benz, Michel Mayor, Daniel Rouan, Didier Queloz, C. Lovis, Damien Ségransan, Günther Wuchterl, Hans J. Deeg, M. Auvergne, Francesco Pepe, M. Hartmann, Laurent Jorda, A. Léger, Helmut Lammer, Heike Rauer, Antoine Llebaria, Pascal Bordé, Martin Pätzold, Tsevi Mazeh, M. Barbieri, Magali Deleuil, Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), Université Nice Sophia Antipolis (... - 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 Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Rotation period, 010504 meteorology & atmospheric sciences, photometry, Astrophysics, 01 natural sciences, 7. Clean energy, Planet, Neptune, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Circular orbit, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Physics, Starspot, Astronomy, Astronomy and Astrophysics, Planetary system, Radial velocity, CoRoT, Amplitude, exoplanets, 13. Climate action, Space and Planetary Science, transit method, terrestrial planets, CoRoT-7, Astrophysics::Earth and Planetary Astrophysics, super-Earth
Abstract: We report on an intensive observational campaign carried out with HARPS at the 3.6 m telescope at La Silla on the star CoRoT-7. Additional simultaneous photometric measurements carried out with the Euler Swiss telescope have demonstrated that the observed radial velocity variations are dominated by rotational modulation from cool spots on the stellar surface. Several approaches were used to extract the radial velocity signal of the planet(s) from the stellar activity signal. First, a simple pre-whitening procedure was employed to find and subsequently remove periodic signals from the complex frequency structure of the radial velocity data. The dominant frequency in the power spectrum was found at 23 days, which corresponds to the rotation period of CoRoT-7. The 0.8535 day period of CoRoT-7b planetary candidate was detected with an amplitude of 3.3 m s −1 . Most other frequencies, some with amplitudes larger than the CoRoT-7b signal, are most likely associated with activity. A second approach used harmonic decomposition of the rotational period and up to the first three harmonics to filter out the activity signal from radial velocity variations caused by orbiting planets. After correcting the radial velocity data for activity, two periodic signals are detected: the CoRoT-7b transit period and a second one with a period of 3.69 days and an amplitude of 4 m s −1 . This second signal was also found in the pre-whitening analysis. We attribute the second signal to a second, more remote planet CoRoT-7c . The orbital solution of both planets is compatible with circular orbits. The mass of CoRoT-7b is 4.8 ± 0. 8( M⊕) and that of CoRoT-7c is 8.4 ± 0. 9( M⊕), assuming both planets are on coplanar orbits. We also investigated the false positive scenario of a blend by a faint stellar binary, and this may be rejected by the stability of the bisector on a nightly scale. According to their masses both planets belong to the super-Earth planet category. The average density of CoRoT-7b is ρ = 5.6 ± 1. 3gc m −3 , similar to the Earth. The CoRoT-7 planetary system provides us with the first insight into the physical nature of short period super-Earth planets recently detected by radial velocity surveys. These planets may be denser than Neptune and therefore likely made of rocks like the Earth, or a mix of water ice and rocks.
Published: 2009
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30. Non-radial oscillation modes with long lifetimes in giant stars

Author: Fabien Carrier, Thomas Kallinger, Pierre Barge, Saskia Hekker, Werner W. Weiss, A. Baglin, Artie P. Hatzes, Frédéric Baudin, Magali Deleuil, C. Barban, Reza Samadi, Joris De Ridder, M. Auvergne, Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, 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, 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, Institut d'astrophysique spatiale (IAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Thüringer Landessternwarte, Tautenburg Observatory, Observatoire Royal de Belgique (ORB), Institut für Astronomie, Universität Wien (IfA), 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: Physics, Multidisciplinary, Red giant, Bright giant, Stellar collision, Astronomy, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Horizontal branch, Stars, Astrophysics::Solar and Stellar Astrophysics, Stellar structure, Astrophysics::Earth and Planetary Astrophysics, Solar-like oscillations, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Stellar evolution, Astrophysics::Galaxy Astrophysics
Abstract: When main-sequence stars like the Sun near the end of their life, they expand to become oscillating red giants. Such evolved stars could in principle provide stringent tests of stellar theory via analysis of radial and non-radial stellar oscillations. Until now it has been unclear whether non-radial modes are observable at all in red giants. De Ridder et al. now report the presence of both radial and non-radial oscillations in over 300 giant stars. For some red giants, mode lifetimes are of the order of a month. Current stellar evolution theory cannot account for these observations. Towards the end of their lives, stars like the Sun expand greatly to become red giant stars that oscillate. Such evolved stars could provide stringent tests of stellar theory through the analysis of radial and non-radial stellar oscillations. Here, the presence of such oscillations in more than 300 giant stars is reported, with mode lifetimes of some of the giants in the order of a month. Towards the end of their lives, stars like the Sun greatly expand to become red giant stars. Such evolved stars could provide stringent tests of stellar theory, as many uncertainties of the internal stellar structure accumulate with age. Important examples are convective overshooting and rotational mixing during the central hydrogen-burning phase, which determine the mass of the helium core, but which are not well understood1. In principle, analysis of radial and non-radial stellar oscillations can be used to constrain the mass of the helium core. Although all giants are expected to oscillate2, it has hitherto been unclear whether non-radial modes are observable at all in red giants, or whether the oscillation modes have a short or a long mode lifetime3,4,5,6,7, which determines the observational precision of the frequencies. Here we report the presence of radial and non-radial oscillations in more than 300 giant stars. For at least some of the giants, the mode lifetimes are of the order of a month. We observe giant stars with equally spaced frequency peaks in the Fourier spectrum of the time series, as well as giants for which the spectrum seems to be more complex. No satisfactory theoretical explanation currently exists for our observations.
Published: 2009
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31. Transiting exoplanets from the CoRoT space mission VI. CoRoT-Exo-3b: the first secure inhabitant of the brown-dwarf desert

Author: M. Deleuil, H. J. Deeg, R. Alonso, F. Bouchy, D. Rouan, M. Auvergne, A. Baglin, S. Aigrain, J. M. Almenara, M. Barbieri, P. Barge, H. Bruntt, P. Bordé, A. Collier Cameron, Sz. Csizmadia, R. De la Reza, R. Dvorak, A. Erikson, M. Fridlund, D. Gandolfi, M. Gillon, E. Guenther, T. Guillot, A. Hatzes, G. Hébrard, L. Jorda, H. Lammer, A. Léger, A. Llebaria, B. Loeillet, M. Mayor, T. Mazeh, C. Moutou, M. Ollivier, M. Pätzold, F. Pont, D. Queloz, H. Rauer, J. Schneider, A. Shporer, G. Wuchterl, S. Zucker, Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), Université Nice Sophia Antipolis (... - 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, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-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), Instituto de Astrofísica de Canarias (IAC), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-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), Pôle Astronomie du LESIA, 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, School of Physics, University of Exeter, School of physics, University of New South Wales, Institut d'astrophysique spatiale (IAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), School of Physics and Astronomy, University of St Andrews, Institute of Planetary Research, Deutsches Zentrum für Luft- und Raumfahrt (DLR), Observatório Nacional/MCTI, Institut für Astronomie, Universität Wien (IfA), Research and Scientific Support Department, ESA-ESTEC (RSSD), Thüringer Landessternwarte, Tautenburg Observatory, Observatoire Astronomique de l'Université de Genève, Observatoire de la Côte d'Azur (OCA), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut für Weltraumforschung, Österreichische Akademie der Wissenschaften (IWF), School of Physics and Astronomy, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Rheinisches Institut für Umweltforschung an der Universität zu Köln (RIU), Laboratoire Univers et Théories (LUTH (UMR_8102)), and Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris
Subjects: photometry, Population, Brown dwarf, FOS: Physical sciences, Astrophysics, 01 natural sciences, Planet, 0103 physical sciences, Substellar object, education, 010303 astronomy & astrophysics, brown dwarf, Physics, education.field_of_study, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Astrophysics (astro-ph), Astronomy and Astrophysics, Surface gravity, Light curve, Orbital period, Exoplanet, CoRoT, exoplanets, transit method, [SDU]Sciences of the Universe [physics], Space and Planetary Science, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: Context. The CoRoT space mission routinely provides high-precision photometric measurements of thousands of stars that have been continuously observed for months. Aims. The discovery and characterization of the first very massive transiting planetary companion with a short orbital period is reported. Methods. A series of 34 transits was detected in the CoRoT light curve of an F3V star, observed from May to October 2007 for 152 days. The radius was accurately determined and the mass derived for this new transiting, thanks to the combined analysis of the light curve and complementary ground-based observations: high-precision radial-velocity measurements, on-off photometry, and high signal-to-noise spectroscopic observations. Results. CoRoT-Exo-3b has a radius of 1.01+-0.07 RJup and transits around its F3-type primary every 4.26 days in a synchronous orbit. Its mass of 21.66+-1.0 MJup, density of 26.4+-5.6 g cm^-3, and surface gravity of log g = 4.72 clearly distinguish it from the regular close-in planet population, making it the most intriguing transiting substellar object discovered so far. Conclusions. With the current data, the nature of CoRoT-Exo-3b is ambiguous, as it could either be a low-mass brown-dwarf or a member of a new class of "superplanets". Its discovery may help constrain the evolution of close-in planets and brown-dwarfs better. Finally, CoRoT-Exo-3b confirms the trend that massive transiting giant planets (M >= 4 MJup) are found preferentially around more massive stars than the Sun., 11 pages, 12 figures, accepted for A&A
Published: 2008
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32. CoRoT sounds the stars: p-mode parameters of Sun-like oscillations on HD 49933

Author: J. Ballot, Reza Samadi, C. Régulo, T. Toutain, William J. Chaplin, C. Barban, Hans Kjeldsen, A. Baglin, Sébastien Deheuvels, J. C. Hulot, Frédéric Baudin, Rafael A. García, Thierry Appourchaux, S. J. Jiménez-Reyes, M. Auvergne, Eric Michel, Graham A. Verner, Patrick Boumier, Ian W. Roxburgh, Benoit Mosser, Yvonne Elsworth, Othman Benomar, Institut d'astrophysique spatiale (IAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (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), Pôle Astronomie du LESIA, 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, Pôle Planétologie du LESIA, 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)-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), School of Physics and Astronomy, University of Birmingham, Astronomy Unit, Queen Mary, Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Max-Planck-Institut für Astrophysik (MPA), Instituto de Astrofísica de Canarias (IAC), and Danish AsteroSeismology Centre (DASC)
Subjects: Physics, Overtone, Mode (statistics), Spectral density, Astronomy and Astrophysics, Context (language use), Astrophysics, Light curve, Asteroseismology, Amplitude, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Solar-like oscillations, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: International audience; Context: The first asteroseismology results from CoRoT are presented, on a star showing Sun-like oscillations. We have analyzed a 60 day lightcurve of high-quality photometric data collected by CoRoT on the F5 V star HD 49933. The data reveal a rich spectrum of overtones of low-degree p modes. Aims: Our aim was to extract robust estimates of the key parameters of the p modes observed in the power spectrum of the lightcurve. Methods: Estimation of the mode parameters was performed using maximum likelihood estimation of the power spectrum. A global fitting strategy was adopted whereby 15 mode orders of the mode spectrum (45 modes) were fitted simultaneously. Results: The parameter estimates that we list include mode frequencies, peak linewidths, mode amplitudes, and a mean rotational frequency splitting. We find that the average large frequency (overtone) spacing derived from the fitted mode frequencies is 85.9 ± 0.15 muHz. The frequency of maximum amplitude of the radial modes is at 1760 muHz, where the observed rms mode amplitude is 3.75 ± 0.23 ppm. The mean rotational splitting of the non-radial modes appears to be in the range ≈2.7 muHz to ≈3.4 muHz. The angle of inclination offered by the star, as determined by fits to the amplitude ratios of the modes, appears to be in the range ≈50 degrees to ≈62 degrees.
Published: 2008
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33. CoRoT measures solar-like oscillations and granulation in stars hotter than the Sun

Author: Yveline Lebreton, Ignasi Ribas, Marie-Jo Goupil, C. Catala, Sylvie Vauclair, Philippe Mathias, Coralie Neiner, Malcolm Fridlund, R. Garrido, J. Ballot, Michel Rieutord, Patrick Boumier, Marc-Antoine Dupret, Werner W. Weiss, Conny Aerts, Gabrielle Berthomieu, G. Vauclair, Annie Baglin, Stéphane Charpinet, Frédéric Baudin, R. Samadi, T. Toutain, Eduardo Janot-Pacheco, Rafael A. García, Ian W. Roxburgh, Konstanze Zwintz, Didier Tiphène, M. Auvergne, Thierry Appourchaux, Anne-Marie Hubert, Sylvaine Turck-Chièze, B. Mosser, François Lignières, Eric Michel, Mário J. P. F. G. Monteiro, Caroline Barban, A. Grotsch-Noels, Hans Kjeldsen, G. Alecian, Janine Provost, José Renan de Medeiros, Teodoro Roca Cortés, Anne Thoul, Ennio Poretti, Faculdade de Ciências, 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), Laboratoire Astrophysique de Toulouse-Tarbes (LATT), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)
Subjects: Convection, Astronomy, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Rotation, 01 natural sciences, Asteroseismology, Solar-Like Oscillations, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Stars hotter than the sun, Solar-like oscillations, Helioseismology, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, Multidisciplinary, Astrofísica, Ciências Físicas, Astronomia, 010308 nuclear & particles physics, Oscillation, Astrophysics (astro-ph), Astrophysics, Physical sciences, Astronomy, CoRoT (Convection Rotation and Planetary Transits) satellite, Stars, Stellar granulation, ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, [SDU.ASTR.GA]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], Astrophysics::Earth and Planetary Astrophysics, Main sequence
Abstract: 4 pages, 3 figures.-- Supporting Online Material: Text, Fig. S1, Table S1 and References, available at: http://www.sciencemag.org/cgi/content/full/322/5901/558/DC1, Oscillations of the Sun have been used to understand its interior structure. The extension of similar studies to more distant stars has raised many difficulties despite the strong efforts of the international community over the past decades. The CoRoT (Convection Rotation and Planetary Transits) satellite, launched in December 2006, has now measured oscillations and the stellar granulation signature in three main sequence stars that are noticeably hotter than the sun. The oscillation amplitudes are about 1.5 times as large as those in the Sun; the stellar granulation is up to three times as high. The stellar amplitudes are about 25% below the theoretic values, providing a measurement of the nonadiabaticity of the process ruling the oscillations in the outer layers of the stars.
Published: 2008
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34. Radiation effects on space-based stellar photometry: theoretical models and empirical results for CoRoT Space Telescope

Author: L. Pinheiro da Silva, G. Rolland, V. Lapeyrere, M. Auvergne, 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, 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, Ingénieurs, Techniciens et Administratifs, Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), and Centre National d'Études Spatiales [Toulouse] (CNES)
Subjects: Physics, Earth's orbit, education.field_of_study, Population, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astronomy and Astrophysics, Astrophysics, Asteroseismology, Exoplanet, law.invention, Telescope, Radiation flux, Photometry (astronomy), Spitzer Space Telescope, Space and Planetary Science, law, [SDU]Sciences of the Universe [physics], Physics::Space Physics, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, education, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: Convection, Rotation and planetary Transits (CoRoT) is a space mission dedicated to stellar seismology and the search for extrasolar planets. Both scientific programs are based on very high precision photometry and require long, uninterrupted observations. The instrument is based on an afocal telescope and a wide-field camera, consisting of four E2V-4280 CCD devices. This set is mounted on a recurrent platform for insertion in low Earth orbit. The CoRoT satellite has been recently launched for a nominal mission duration of three years. In this work, we discuss the impact of space radiation on CoRoT CCDs, in sight of the in-flight characterization results obtained during the satellite's commissioning phase, as well as the very first observational data. We start by describing the population of trapped particles at the satellite altitude, and by presenting a theoretical prediction for the incoming radiation fluxes seen by the CCDs behind shielding. Empirical results regarding particle impact rates and their geographical distribution are then presented and discussed. The effect of particle impacts is also statistically characterized, with respect to the ionizing energy imparted to the CCDs and the size of impact trails. Based on these results, we discuss the effects of space radiation on precise and time-resolved stellar photometry from space. Finally, we present preliminary results concerning permanent radiation damage on CoRoT CCDs, as extrapolated from the data available at the beginning of the satellite's lifetime.
Published: 2008
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35. Comparative blind test of five planetary transit detection algorithms on realistic synthetic light curves

Author: Pierre Barge, Holger Voss, Frederic Pont, C. Moutou, P. Guterman, Suzanne Aigrain, R. Cautain, Antonino F. Lanza, D. Blouin, M. Auvergne, V. Guis, D. Queloz, Heike Rauer, Anders Erikson, Mike Irwin, Shay Zucker, 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), Observatoire Astronomique de l'Université de Genève, Institute of Astronomy, University of Cambridge (IoA), 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), DLR Institut für Planetenerkundung, Gemplus, and INAF-Osservatorio Astrofisico di Catania (INAF-OACt)
Subjects: Physics, Astronomy, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Planetary system, Light curve, Orbital period, Exoplanet, Stars, planetary systems -- methods: data analysis -- techniques: photometric -- methods: observational, Space and Planetary Science, Planet, Binary star, Astrophysics::Solar and Stellar Astrophysics, Transit (astronomy), Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Algorithm
Abstract: Because photometric surveys of exoplanet transits are very promising sources of future discoveries, many algorithms are being developed to detect transit signals in stellar light curves. This paper compares such algorithms for the next generation of space-based transit detection surveys like CoRoT, Kepler, and Eddington, Five independent analyses of a thousand synthetic light curves are presented. The light curves were produced with an end-to-end instrument simulator and include stellar microvariability and a varied sample of stellar and planetary transits diluted within a much larger set of light curves. The results show that different algorithms perform quite differently, with varying degrees of success in detecting real transits and avoiding false positives. We also find that the detection algorithm alone does not make all the difference, as the way the light curves are filtered and detrended beforehand also has a strong impact on the detection limit and on the false alarm rate. The microvariability of sun-like stars is a limiting factor only in extreme cases, when the fluctuation amplitudes are large and the star is faint. In the majority of cases it does not prevent detection of planetary transits. The most sensitive analysis is performed with periodic box-shaped detection filters. False positives are method-dependent, which should allow reduction of their detection rate in real surveys. Background eclipsing binaries are wrongly identified as planetary transits in most cases, a result which confirms that contamination by background stars is the main limiting factor. With parameters simulating the CoRoT mission, our detection test indicates that the smallest detectable planet radius is on the order of 2 Earth radii for a 10-day orbital period planet around a KO dwarf. © ESO 2005.
Published: 2005
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36. A Search for Small Kuiper Belt Objects by Stellar Occultations

Author: M. Moncuquet, Françoise Roques, Jean Lecacheux, N. Lavillonière, F. Colas, M. Chevreton, M. Auvergne, 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, 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, Physique des plasmas, Pôle Planétologie du LESIA, 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)-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 Paris Cité (UPCité)
Subjects: Physics, Flux, Astronomy and Astrophysics, Photometer, Astrophysics, Radius, law.invention, Space and Planetary Science, Observatory, law, Stellar occultation, Formation and evolution of the Solar System, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Event (particle physics)
Abstract: We report the conditions and results of an observation campaign organized in 2000 September at the Pic du Midi Observatory, and dedicated for the first time to the study of Kuiper belt objects (KBOs) by stellar occultations. The observation consisted of recording the flux of a well-chosen star with a fast photometer (20 Hz) and counting occultations of this star by passing KBOs. The campaign provided 15 hr of good-quality signal (rms σ ~ 1.8%) and zero detections of KBOs at a 4 σ detection level. For a KBO differential size distribution assumed to vary as r-q, this first result suggests a slope q 4.5. A refined analysis of the data, studying diffraction patterns, allowed us to find an event at a 3 σ detection level compatible with a 150 m KBO. More generally, observation campaigns of stellar occultation by KBOs on ≥2 m class telescopes could statistically constrain the slope and the expected turnover radius due to collisional erosion of the subkilometer KBO size distribution.
Published: 2003
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37. Seismic analysis of HD 43587Aa, a solar-like oscillator in a multiple system

Author: T. Stahn, S. Mathur, R. Samadi, S. Hekker, Laurent Gizon, T. Appourchaux, Yveline Lebreton, C. Catala, Patrick Gaulme, Othman Benomar, M. Hall, P. Boumier, Ian W. Roxburgh, Clara Régulo, Graham A. Verner, E. Poretti, B. Mosser, T. Morel, A. Baglin, F. Baudin, J. D. do Nascimento, D. Salabert, M. Auvergne, R. A. Garcia, E. Michel, William J. Chaplin, Yvonne Elsworth, M. Rainer, S. Chaintreuil, Low Energy Astrophysics (API, FNWI), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information (CEA-LETI), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Galaxies, Etoiles, Physique, Instrumentation (GEPI), 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), Institut de Physique de Rennes (IPR), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), School of Physics and Astronomy, University of Birmingham [Birmingham], 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), Insituto Geofísico, Escuela Politécnica Nacional (EPN), 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 de Liège, INAF - Osservatorio Astronomico di Brera (OAB), Istituto Nazionale di Astrofisica (INAF), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), 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: 010504 meteorology & atmospheric sciences, stars: individual: HD 43587Aa, FOS: Physical sciences, Orbital eccentricity, Astrophysics, asteroseismology, Star (graph theory), stars, HD 43587Aa, binaries, solar-type, data analysis, Rotation, 01 natural sciences, Apparent magnitude, Planet, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), 0105 earth and related environmental sciences, Physics, Astronomy and Astrophysics, stars: solar-type, Radius, Effective temperature, methods: data analysis, [PHYS.PHYS.PHYS-GEN-PH]Physics [physics]/Physics [physics]/General Physics [physics.gen-ph], Radial velocity, binaries: general, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: Context. The object HD 43587Aa is a G0V star observed during the 145-day LRa03 run of the COnvection, ROtation and planetary Transits space mission (CoRoT), for which complementary High Accuracy Radial velocity Planet Searcher (HARPS) spectra with S/N > 300 were also obtained. Its visual magnitude is 5.71, and its effective temperature is close to 5950 K. It has a known companion in a highly eccentric orbit and is also coupled with two more distant companions.Aims. We undertake a preliminary investigation of the internal structure of HD 43587Aa.Methods. We carried out a seismic analysis of the star, using maximum likelihood estimators and Markov chain Monte Carlo methods.Results. We established the first table of the eigenmode frequencies, widths, and heights for HD 43587Aa. The star appears to have a mass and a radius slightly larger than the Sun, and is slightly older (5.6 Gyr). Two scenarios are suggested for the geometry of the star: either its inclination angle is very low, or the rotation velocity of the star is very low.Conclusions. A more detailed study of the rotation and of the magnetic and chromospheric activity for this star is needed, and will be the subject of a further study. New high resolution spectrometric observations should be performed for at least several months in duration.
Published: 2014
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38. Transcriptional Differences between Normal and Glioma-Derived Glial Progenitor Cells Identify a Core Set of Dysregulated Genes

Author: Romane M. Auvergne, Fraser J. Sim, Su Wang, Devin Chandler-Militello, Jaclyn Burch, Yazan Al Fanek, Danielle Davis, Abdellatif Benraiss, Kevin Walter, Pragathi Achanta, Mahlon Johnson, Alfredo Quinones-Hinojosa, Sridaran Natesan, Heide L. Ford, and Steven A. Goldman
Subjects: Biology (General), QH301-705.5
Abstract: Glial progenitor cells (GPCs) are a potential source of malignant gliomas. We used A2B5-based sorting to extract tumorigenic GPCs from human gliomas spanning World Health Organization grades II–IV. Messenger RNA profiling identified a cohort of genes that distinguished A2B5+ glioma tumor progenitor cells (TPCs) from A2B5+ GPCs isolated from normal white matter. A core set of genes and pathways was substantially dysregulated in A2B5+ TPCs, which included the transcription factor SIX1 and its principal cofactors, EYA1 and DACH2. Small hairpin RNAi silencing of SIX1 inhibited the expansion of glioma TPCs in vitro and in vivo, suggesting a critical and unrecognized role of the SIX1-EYA1-DACH2 system in glioma genesis or progression. By comparing the expression patterns of glioma TPCs with those of normal GPCs, we have identified a discrete set of pathways by which glial tumorigenesis may be better understood and more specifically targeted.
Published: 2013
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39. Efficacy and Safety of Erenumab in Participants With Episodic Migraine in Whom 2-4 Prior Preventive Treatments Had Failed: LIBERTY 3-Year Study.

Author: Reuter U, Goadsby PJ, Ferrari MD, Da Silva Lima GP, Mondal S, Kalim J, Hasan F, Wen S, Arkuszewski M, Pandhi S, Stites T, and Lanteri-Minet M
Subjects: Humans, Male, Female, Double-Blind Method, Adult, Middle Aged, Treatment Failure, Treatment Outcome, Antibodies, Monoclonal, Humanized therapeutic use, Antibodies, Monoclonal, Humanized adverse effects, Migraine Disorders drug therapy, Migraine Disorders prevention & control, Calcitonin Gene-Related Peptide Receptor Antagonists therapeutic use, Calcitonin Gene-Related Peptide Receptor Antagonists adverse effects, Calcitonin Gene-Related Peptide Receptor Antagonists administration & dosage, Calcitonin Gene-Related Peptide Receptor Antagonists pharmacology
Abstract: Background and Objectives: The LIBERTY study assessed the efficacy and safety of erenumab in participants with episodic migraine (EM) and 2-4 prior preventive treatment failures. The results have been presented after 3 years of erenumab exposure in its open-label extension phase (OLEP)., Methods: Participants completing the 12-week double-blind treatment phase (DBTP) of the LIBERTY study could enter the OLEP and receive 140 mg of erenumab once monthly for 3 years. The main outcomes included the proportion of participants achieving ≥50% reduction in monthly migraine days (MMDs), the mean MMD change from baseline, and tolerability and safety., Results: Overall, 240/246 (97.6%) participants entered the OLEP and 168/240 (70.0%) completed the study (85/118 continuing erenumab [n = 1 lost during follow-up]; 83/122 switching from placebo [n = 2 lost during follow-up]). In the overall population, 79/151 participants (52.3%) with valid data points achieved ≥50% reduction in MMDs at week 168 (i.e., responders). In the continuous erenumab group, 35/117 participants (29.9%) were ≥50% responders at week 12 of the DBTP and 26/35 (74.3%) remained ≥50% responders in at least half of OLEP visits. Of the 82/117 participants (70.1%) not achieving responder status at week 12 in the continuous erenumab group, 17/82 (20.7%) converted to ≥50% responders in at least half of OLEP visits. Of 103/120 participants (85.8%) not achieving responder status at week 12 in the placebo-erenumab group, 42/103 (40.8%) converted to ≥50% responders in at least half of OLEP visits after switching to erenumab. Overall, the mean (SD) MMD change from baseline showed sustained improvement over 3 years (-4.4 [3.9] days at week 168). The most common treatment-emergent AEs (per 100 person-years) were nasopharyngitis (28.8), influenza (7.5), and back pain (5.8). Overall, 9.6% (3.9 per 100 person-years) and 6.7% (2.7 per 100 person-years) of participants reported events of treatment-emergent hypertension and constipation, respectively. The safety and tolerability profile remained consistent with earlier studies., Discussion: Erenumab (140 mg) showed sustained efficacy over 3 years in participants with EM and 2-4 prior preventive treatment failures. No new safety signals were observed., Trial Registration Information: ClinicalTrials.gov Identifier: NCT03096834.
Published: 2024
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40. Long-term Efficacy and Safety of Erenumab: Results From 64 Weeks of the LIBERTY Study.

Author: Goadsby PJ, Reuter U, Lanteri-Minet M, Paiva da Silva Lima G, Hours-Zesiger P, Fernandes C, Wen S, Tenenbaum N, Kataria A, Ferrari MD, and Klatt J
Abstract: Objective: To report the efficacy and safety of erenumab among patients with episodic migraine (EM) who were unsuccessful on 2 to 4 preventive treatments observed at week 64 of the open-label extension phase (OLEP) of A Study Evaluating the Effectiveness of AMG 334 Injection in Preventing Migraines in Adults Having Failed Other Therapies (LIBERTY) study (ClinicalTrials.gov NCT03096834)., Methods: The OLEP, evaluating monthly erenumab 140 mg for 3 years, enrolled 240 patients who completed the double-blind treatment phase (DBTP) of 12 weeks during which they received placebo or erenumab 140 mg subcutaneous injections every 4 weeks as monotherapy. Efficacy outcomes were evaluated through the initial 52 weeks of OLEP (from DBTP baseline to total 64 weeks) in the overall population, patients receiving erenumab in DBTP, and patients from the DBTP placebo arm who switched to erenumab in OLEP. Endpoints included reduction of ≥50% in monthly migraine days (MMD) from DBTP baseline and change in MMD from DBTP baseline, Headache Impact Test score, and Migraine Physical Function Impact Diary score (Physical Impairment and Everyday Activities)., Results: Altogether, the week 52 visit of the OLEP was completed by 204 of 240 (85.0%) patients. Among patients continuing erenumab, the 50% responder rate increased from 29.9% at weeks 9 to 12 to 44.3% at weeks 61 to 64. The 50% responder rate in patients who initiated erenumab in the OLEP remained higher in the OLEP (50.0% at week 61-64) than during DBTP (14.2% at weeks 9-12) compared to patients in continuous erenumab arm. In the OLEP, the 50% responder rate for the overall population increased from weeks 13 to 16 until weeks 37 to 40 and then remained stable through weeks 61 to 64. Patients treated with erenumab in DBTP showed sustained effects on all efficacy outcomes; those initiating erenumab in the OLEP demonstrated continued improvement from week 13 onward. Adverse events (AEs) were reported, considering both treatment groups, by ≈80.8% (serious AEs by 6.7%), 76.3% (5.9%) in the continuing erenumab arm, and 85.2% (7.4%) in those starting erenumab in OLEP. No deaths were reported., Conclusions: In patients with EM who were unsuccessful on 2 to 4 prior preventive treatments, the LIBERTY study demonstrated sustained efficacy on erenumab monotherapy treatment through 64 weeks in both treatment arms. Safety of erenumab was consistent with that observed in previous clinical trials., Trial Registration Information: ClinicalTrials.govIdentifier: NCT03096834., Classification of Evidence: The current study provides Class IV evidence on data from patients with EM that erenumab is safe and provides sustained efficacy at 52 weeks., (Copyright © 2021 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Neurology.)
Published: 2021
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41. Seismic constraints on rotation of Sun-like star and mass of exoplanet.

Author: Gizon L, Ballot J, Michel E, Stahn T, Vauclair G, Bruntt H, Quirion PO, Benomar O, Vauclair S, Appourchaux T, Auvergne M, Baglin A, Barban C, Baudin F, Bazot M, Campante T, Catala C, Chaplin W, Creevey O, Deheuvels S, Dolez N, Elsworth Y, García R, Gaulme P, Mathis S, Mathur S, Mosser B, Régulo C, Roxburgh I, Salabert D, Samadi R, Sato K, Verner G, Hanasoge S, and Sreenivasan KR
Subjects: Astronomy, Models, Theoretical, Planets, Rotation, Stars, Celestial
Abstract: Rotation is thought to drive cyclic magnetic activity in the Sun and Sun-like stars. Stellar dynamos, however, are poorly understood owing to the scarcity of observations of rotation and magnetic fields in stars. Here, inferences are drawn on the internal rotation of a distant Sun-like star by studying its global modes of oscillation. We report asteroseismic constraints imposed on the rotation rate and the inclination of the spin axis of the Sun-like star HD 52265, a principal target observed by the CoRoT satellite that is known to host a planetary companion. These seismic inferences are remarkably consistent with an independent spectroscopic observation (rotational line broadening) and with the observed rotation period of star spots. Furthermore, asteroseismology constrains the mass of exoplanet HD 52265b. Under the standard assumption that the stellar spin axis and the axis of the planetary orbit coincide, the minimum spectroscopic mass of the planet can be converted into a true mass of 1.85(-0.42)(+0.52)M(Jupiter), which implies that it is a planet, not a brown dwarf.
Published: 2013
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42. A transiting giant planet with a temperature between 250 K and 430 K.

Author: Deeg HJ, Moutou C, Erikson A, Csizmadia S, Tingley B, Barge P, Bruntt H, Havel M, Aigrain S, Almenara JM, Alonso R, Auvergne M, Baglin A, Barbieri M, Benz W, Bonomo AS, Bordé P, Bouchy F, Cabrera J, Carone L, Carpano S, Ciardi D, Deleuil M, Dvorak R, Ferraz-Mello S, Fridlund M, Gandolfi D, Gazzano JC, Gillon M, Gondoin P, Guenther E, Guillot T, den Hartog R, Hatzes A, Hidas M, Hébrard G, Jorda L, Kabath P, Lammer H, Léger A, Lister T, Llebaria A, Lovis C, Mayor M, Mazeh T, Ollivier M, Pätzold M, Pepe F, Pont F, Queloz D, Rabus M, Rauer H, Rouan D, Samuel B, Schneider J, Shporer A, Stecklum B, Street R, Udry S, Weingrill J, and Wuchterl G
Abstract: Of the over 400 known exoplanets, there are about 70 planets that transit their central star, a situation that permits the derivation of their basic parameters and facilitates investigations of their atmospheres. Some short-period planets, including the first terrestrial exoplanet (CoRoT-7b), have been discovered using a space mission designed to find smaller and more distant planets than can be seen from the ground. Here we report transit observations of CoRoT-9b, which orbits with a period of 95.274 days on a low eccentricity of 0.11 +/- 0.04 around a solar-like star. Its periastron distance of 0.36 astronomical units is by far the largest of all transiting planets, yielding a 'temperate' photospheric temperature estimated to be between 250 and 430 K. Unlike previously known transiting planets, the present size of CoRoT-9b should not have been affected by tidal heat dissipation processes. Indeed, the planet is found to be well described by standard evolution models with an inferred interior composition consistent with that of Jupiter and Saturn.
Published: 2010
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43. Deviations from a uniform period spacing of gravity modes in a massive star.

Author: Degroote P, Aerts C, Baglin A, Miglio A, Briquet M, Noels A, Niemczura E, Montalban J, Bloemen S, Oreiro R, Vucković M, Smolders K, Auvergne M, Baudin F, Catala C, and Michel E
Abstract: The life of a star is dominantly determined by the physical processes in the stellar interior. Unfortunately, we still have a poor understanding of how the stellar gas mixes near the stellar core, preventing precise predictions of stellar evolution. The unknown nature of the mixing processes as well as the extent of the central mixed region is particularly problematic for massive stars. Oscillations in stars with masses a few times that of the Sun offer a unique opportunity to disentangle the nature of various mixing processes, through the distinct signature they leave on period spacings in the gravity mode spectrum. Here we report the detection of numerous gravity modes in a young star with a mass of about seven solar masses. The mean period spacing allows us to estimate the extent of the convective core, and the clear periodic deviation from the mean constrains the location of the chemical transition zone to be at about 10 per cent of the radius and rules out a clear-cut profile.
Published: 2010
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44. Solar-like oscillations in a massive star.

Author: Belkacem K, Samadi R, Goupil MJ, Lefèvre L, Baudin F, Deheuvels S, Dupret MA, Appourchaux T, Scuflaire R, Auvergne M, Catala C, Michel E, Miglio A, Montalban J, Thoul A, Talon S, Baglin A, and Noels A
Abstract: Seismology of stars provides insight into the physical mechanisms taking place in their interior, with modes of oscillation probing different layers. Low-amplitude acoustic oscillations excited by turbulent convection were detected four decades ago in the Sun and more recently in low-mass main-sequence stars. Using data gathered by the Convection Rotation and Planetary Transits mission, we report here on the detection of solar-like oscillations in a massive star, V1449 Aql, which is a known large-amplitude (beta Cephei) pulsator.
Published: 2009
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45. Non-radial oscillation modes with long lifetimes in giant stars.

Author: De Ridder J, Barban C, Baudin F, Carrier F, Hatzes AP, Hekker S, Kallinger T, Weiss WW, Baglin A, Auvergne M, Samadi R, Barge P, and Deleuil M
Abstract: Towards the end of their lives, stars like the Sun greatly expand to become red giant stars. Such evolved stars could provide stringent tests of stellar theory, as many uncertainties of the internal stellar structure accumulate with age. Important examples are convective overshooting and rotational mixing during the central hydrogen-burning phase, which determine the mass of the helium core, but which are not well understood. In principle, analysis of radial and non-radial stellar oscillations can be used to constrain the mass of the helium core. Although all giants are expected to oscillate, it has hitherto been unclear whether non-radial modes are observable at all in red giants, or whether the oscillation modes have a short or a long mode lifetime, which determines the observational precision of the frequencies. Here we report the presence of radial and non-radial oscillations in more than 300 giant stars. For at least some of the giants, the mode lifetimes are of the order of a month. We observe giant stars with equally spaced frequency peaks in the Fourier spectrum of the time series, as well as giants for which the spectrum seems to be more complex. No satisfactory theoretical explanation currently exists for our observations.
Published: 2009
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46. CoRoT measures solar-like oscillations and granulation in stars hotter than the Sun.

Author: Michel E, Baglin A, Auvergne M, Catala C, Samadi R, Baudin F, Appourchaux T, Barban C, Weiss WW, Berthomieu G, Boumier P, Dupret MA, Garcia RA, Fridlund M, Garrido R, Goupil MJ, Kjeldsen H, Lebreton Y, Mosser B, Grotsch-Noels A, Janot-Pacheco E, Provost J, Roxburgh IW, Thoul A, Toutain T, Tiphène D, Turck-Chieze S, Vauclair SD, Vauclair GP, Aerts C, Alecian G, Ballot J, Charpinet S, Hubert AM, Lignières F, Mathias P, Monteiro MJ, Neiner C, Poretti E, de Medeiros JR, Ribas I, Rieutord ML, Cortés TR, and Zwintz K
Abstract: Oscillations of the Sun have been used to understand its interior structure. The extension of similar studies to more distant stars has raised many difficulties despite the strong efforts of the international community over the past decades. The CoRoT (Convection Rotation and Planetary Transits) satellite, launched in December 2006, has now measured oscillations and the stellar granulation signature in three main sequence stars that are noticeably hotter than the sun. The oscillation amplitudes are about 1.5 times as large as those in the Sun; the stellar granulation is up to three times as high. The stellar amplitudes are about 25% below the theoretic values, providing a measurement of the nonadiabaticity of the process ruling the oscillations in the outer layers of the stars.
Published: 2008
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