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Your search keyword '"Monteiro, M. J. P. F. G."' showing total 18 results
Start Over Author "Monteiro, M. J. P. F. G." Topic fos: physical sciences
18 results on '"Monteiro, M. J. P. F. G."'

1. A precise architecture characterization of the $��$ Men planetary system

Author

Damasso, M., Sozzetti, A., Lovis, C., Barros, S. C. C., Sousa, S. G., Demangeon, O. D. S., Faria, J. P., Lillo-Box, J., Cristiani, S., Pepe, F., Rebolo, R., Santos, N. C., Osorio, M. R. Zapatero, Hern��ndez, J. I. Gonz��lez, Amate, M., Pasquini, L., Zerbi, F. M., Adibekyan, V., Abreu, M., Affolter, M., Alibert, Y., Aliverti, M., Allart, R., Prieto, C. Allende, ��lvarez, D., Alves, D., Avila, G., Baldini, V., Bandy, T., Benz, W., Bianco, A., Borsa, F., Bossini, D., Bourrier, V., Bouchy, F., Broeg, C., Cabral, A., Calderone, G., Cirami, R., Coelho, J., Conconi, P., Coretti, I., Cumani, C., Cupani, G., D'Odorico, V., Deiries, S., Dekker, H., Delabre, B., Di Marcantonio, P., Dumusque, X., Ehrenreich, D., Figueira, P., Fragoso, A., Genolet, L., Genoni, M., Santos, R. G��nova, Hughes, I., Iwert, O., Kerber, F., Knudstrup, J., Landoni, M., Lavie, B., Lizon, J. -L., Curto, G. Lo, Maire, C., Martins, C. J . A. P., M��gevand, D., Mehner, A., Micela, G., Modigliani, A., Molaro, P., Monteiro, M. A., Monteiro, M. J. P. F. G., Moschetti, M., Mueller, E., Murphy, M. T., Nunes, N., Oggioni, L., Oliveira, A., Oshagh, M., Pall��, E., Pariani, G., Poretti, E., Rasilla, J. L., Rebord��o, J., Redaelli, E. M., Riva, M., Tschudi, S. Santana, Santin, P., Santos, P., S��gransan, D., Schmidt, T. M., Segovia, A., Sosnowska, D., Span��, P., Mascare��o, A. Su��rez, Tabernero, H., Tenegi, F., Udry, S., and Zanutta, A.

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), Astrophysics::Solar and Stellar Astrophysics, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR)
Abstract

The bright star $��$ Men was chosen as the first target for a radial velocity follow-up to test the performance of ESPRESSO, the new high-resolution spectrograph at the ESO's Very-Large Telescope (VLT). The star hosts a multi-planet system (a transiting 4 M$_\oplus$ planet at $\sim$0.07 au, and a sub-stellar companion on a $\sim$2100-day eccentric orbit) which is particularly appealing for a precise multi-technique characterization. With the new ESPRESSO observations, that cover a time span of 200 days, we aim to improve the precision and accuracy of the planet parameters and search for additional low-mass companions. We also take advantage of new photometric transits of $��$ Men c observed by TESS over a time span that overlaps with that of the ESPRESSO follow-up campaign. We analyse the enlarged spectroscopic and photometric datasets and compare the results to those in the literature. We further characterize the system by means of absolute astrometry with Hipparcos and Gaia. We used the spectra of ESPRESSO for an independent determination of the stellar fundamental parameters. We present a precise characterization of the planetary system around $��$ Men. The ESPRESSO radial velocities alone (with typical uncertainty of 10 cm/s) allow for a precise retrieval of the Doppler signal induced by $��$ Men c. The residuals show an RMS of 1.2 m/s, and we can exclude companions with a minimum mass less than $\sim$2 M$_\oplus$ within the orbit of $��$ Men c). We improve the ephemeris of $��$ Men c using 18 additional TESS transits, and in combination with the astrometric measurements, we determine the inclination of the orbital plane of $��$ Men b with high precision ($i_{b}=45.8^{+1.4}_{-1.1}$ deg). This leads to the precise measurement of its absolute mass $m_{b}=14.1^{+0.5}_{-0.4}$ M$_{Jup}$, and shows that the planetary orbital planes are highly misaligned., Accepted for publication on A&A

Published
2020
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2. The first view of $��$ Scuti and $��$ Doradus stars with the TESS mission

Author

Antoci, V., Cunha, M. S., Bowman, D. M., Murphy, S. J., Kurtz, D. W., Bedding, T. R., Borre, C. C., Christophe, S., Daszy��ska-Daszkiewicz, J., Fox-Machado, L., Hern��ndez, A. Garc��a, Ghasemi, H., Handberg, R., Hansen, H., Hasanzadeh, A., Houdek, G., Johnston, C., Justesen, A. B., Alicavus, F. Kahraman, Kotysz, K., Latham, D., Matthews, J. M., M��nster, J., Niemczura, E., Paunzen, E., Arias, J. P. S��nchez, Pigulski, A., Pepper, J., Richey-Yowell, T., Safari, H., Seager, S., Smalley, B., Shutt, T., S��dor, A., Su��rez, J. -C., Tkachenko, A., Wu, T., Zwintz, K., Forteza, S. Barcel��, Brunsden, E., Bogn��r, Z., Buzasi, D. L., Chowdhury, S., De Cat, P., Evans, J. A., Guo, Z., Guzik, J. A., Jevtic, N., Lampens, P., Martiz, M. Lares, Lovekin, C., Li, G., Mirouh, G. M., Mkrtichian, D., Monteiro, M. J. P. F. G., Nemec, J. M., Ouazzani, R., Pascual-Granado, J., Reese, D. R., Rieutord, M., Rodon, J. R., Skarka, M., Sowicka, P., Stateva, I., Szab��, R., and Weiss, W. W.

Subjects
FOS: Physical sciences, Solar and Stellar Astrophysics (astro-ph.SR)
Abstract

We present the first asteroseismic results for $��$ Scuti and $��$ Doradus stars observed in Sectors 1 and 2 of the TESS mission. We utilise the 2-min cadence TESS data for a sample of 117 stars to classify their behaviour regarding variability and place them in the Hertzsprung-Russell diagram using Gaia DR2 data. Included within our sample are the eponymous members of two pulsator classes, $��$ Doradus and SX Phoenicis. Our sample of pulsating intermediate-mass stars observed by TESS also allows us to confront theoretical models of pulsation driving in the classical instability strip for the first time and show that mixing processes in the outer envelope play an important role. We derive an empirical estimate of 74% for the relative amplitude suppression factor as a result of the redder TESS passband compared to the Kepler mission using a pulsating eclipsing binary system. Furthermore, our sample contains many high-frequency pulsators, allowing us to probe the frequency variability of hot young $��$ Scuti stars, which were lacking in the Kepler mission data set, and identify promising targets for future asteroseismic modelling. The TESS data also allow us to refine the stellar parameters of SX Phoenicis, which is believed to be a blue straggler., 33 pages (incl. appendix), accepted for publications in MNRAS

Published
2019
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3. $��$ Centauri A as a potential stellar model calibrator: establishing the nature of its core

Author

Nsamba, B., Monteiro, M. J. P. F. G., Campante, T. L., Cunha, M. S., and Sousa, S. G.

Subjects
Astrophysics::Solar and Stellar Astrophysics, FOS: Physical sciences, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR)
Abstract

Understanding the physical process responsible for the transport of energy in the core of $��$ Centauri A is of the utmost importance if this star is to be used in the calibration of stellar model physics. Adoption of different parallax measurements available in the literature results in differences in the interferometric radius constraints used in stellar modelling. Further, this is at the origin of the different dynamical mass measurements reported for this star. With the goal of reproducing the revised dynamical mass derived by Pourbaix & Boffin, we modelled the star using two stellar grids varying in the adopted nuclear reaction rates. Asteroseismic and spectroscopic observables were complemented with different interferometric radius constraints during the optimisation procedure. Our findings show that best-fit models reproducing the revised dynamical mass favour the existence of a convective core ($\gtrsim$ 70% of best-fit models), a result that is robust against changes to the model physics. If this mass is accurate, then $��$ Centauri A may be used to calibrate stellar model parameters in the presence of a convective core., 6 pages, 2 figures, 4 tables. Accepted for publication in Monthly Notices of the Royal Astronomical Society Letters

Published
2018
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4. The PLATO 2.0 mission

Author

Rauer, H., Catala, C., Aerts, C., Appourchaux, T., Benz, W., Brandeker, A., Christensen-Dalsgaard, J., Deleuil, M., Gizon, L., Goupil, M. -J., G��del, M., Janot-Pacheco, E., Mas-Hesse, M., Pagano, I., Piotto, G., Pollacco, D., Santos, N. C., Smith, A., C., J., Su��rez, Szab��, R., Udry, S., Adibekyan, V., Alibert, Y., Almenara, J. -M., Amaro-Seoane, P., Eiff, M. Ammler-von, Asplund, M., Antonello, E., Ball, W., Barnes, S., Baudin, F., Belkacem, K., Bergemann, M., Bihain, G., Birch, A. C., Bonfils, X., Boisse, I., Bonomo, A. S., Borsa, F., Brand��o, I. M., Brocato, E., Brun, S., Burleigh, M., Burston, R., Cabrera, J., Cassisi, S., Chaplin, W., Charpinet, S., Chiappini, C., Church, R. P., Csizmadia, Sz., Cunha, M., Damasso, M., Davies, M. B., Deeg, H. J., D��az, R. F., Dreizler, S., Dreyer, C., Eggenberger, P., Ehrenreich, D., Eigm��ller, P., Erikson, A., Farmer, R., Feltzing, S., Fialho, F. de Oliveira, Figueira, P., Forveille, T., Fridlund, M., Garc��a, R. A., Giommi, P., Giuffrida, G., Godolt, M., da Silva, J. Gomes, Granzer, T., Grenfell, J. L., Grotsch-Noels, A., G��nther, E., Haswell, C. A., Hatzes, A. P., H��brard, G., Hekker, S., Helled, R., Heng, K., Jenkins, J. M., Johansen, A., Khodachenko, M. L., Kislyakova, K. G., Kley, W., Kolb, U., Krivova, N., Kupka, F., Lammer, H., Lanza, A. F., Lebreton, Y., Magrin, D., Marcos-Arenal, P., Marrese, P. M., Marques, J. P., Martins, J., Mathis, S., Mathur, S., Messina, S., Miglio, A., Montalban, J., Montalto, M., Monteiro, M. J. P. F. G., Moradi, H., Moravveji, E., Mordasini, C., Morel, T., Mortier, A., Nascimbeni, V., Nelson, R. P., Nielsen, M. B., Noack, L., Norton, A. J., Ofir, A., Oshagh, M., Ouazzani, R. -M., P��pics, P., Parro, V. C., Petit, P., Plez, B., Poretti, E., Quirrenbach, A., Ragazzoni, R., Raimondo, G., Rainer, M., Reese, D. R., Redmer, R., Reffert, S., Rojas-Ayala, B., Roxburgh, I. W., Salmon, S., Santerne, A., Schneider, J., Schou, J., Schuh, S., Schunker, H., Silva-Valio, A., Silvotti, R., Skillen, I., Snellen, I., Sohl, F., Sousa, S. G., Sozzetti, A., Stello, D., Strassmeier, K. G., ��vanda, M., Szab��, Gy. M., Tkachenko, A., Valencia, D., van Grootel, V., Vauclair, S. D., Ventura, P., Wagner, F. W., Walton, N. A., Weingrill, J., Werner, S. C., Wheatley, P. J., Zwintz, K., DLR Institut für Planetenforschung, Deutsches Zentrum für Luft- und Raumfahrt [Berlin] (DLR), 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), Instituut voor Sterrenkunde [Leuven], Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), 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), Physikalisches Institut [Bern], Universität Bern [Bern] (UNIBE), Stockholm University, Stellar Astrophysics Centre [Aarhus] (SAC), Aarhus University [Aarhus], Department of Palaeontology, National Institutes of Health [Bethesda] (NIH)-The Natural History Museum (NHM), Laboratoire d'Informatique Avancée de Saint-Denis (LIASD), Université Paris 8 Vincennes-Saint-Denis (UP8), High Speed Networks Laboratory, Dept. of Telecommunications and Media Informatics, Budapest University of Technology and Economics [Budapest] (BME), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève = University of Geneva (UNIGE), Laboratoire d'astrophysique de l'observatoire de Besançon (UMR 6091) (LAOB), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), 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), Université Grenoble Alpes - UFR Pharmacie (UGA UFRP), Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Department of Physics and Astronomy [Leicester], University of Leicester, Institute for Digital Communication Joint Research Institute for Signal & Image Processing School of Engineering and Electronics - University of Edinburgh, University of Edinburgh, Institut d'Astrophysique de Paris (IAP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), DLR Institute of Planetary Research, German Aerospace Center (DLR), UCLA Economics, University of California [Los Angeles] (UCLA), University of California (UC)-University of California (UC), Centro de Astrofísica da Universidade do Porto (CAUP), Universidade do Porto = University of Porto, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG ), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Research and Scientific Support Department, ESTEC (RSSD), European Space Research and Technology Centre (ESTEC), Agence Spatiale Européenne = European Space Agency (ESA)-Agence Spatiale Européenne = European Space Agency (ESA), Nottingham Transportation Engineering Centre, University of Nottingham, UK (UON), Thüringer Landessternwarte Tautenburg (TLS), Tel Aviv University (TAU), Center for Space and Habitability (CSH), University of Bern, Institut de Physique de Rennes (IPR), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Département Langues et Culture Internationale (LCI), Université européenne de Bretagne - European University of Brittany (UEB)-Télécom Bretagne-Institut Mines-Télécom [Paris] (IMT), Space Research Institute of Austrian Academy of Sciences (IWF), Austrian Academy of Sciences (OeAW), School of Physical Sciences [Milton Keynes], Faculty of Science, Technology, Engineering and Mathematics [Milton Keynes], The Open University [Milton Keynes] (OU)-The Open University [Milton Keynes] (OU), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, CTS/UNINOVA, Faculty of Sciences and Technology, Institut d'Astrophysique et de Géophysique [Liège], Université de Liège, School of Physics and Astronomy, University of Birmingham [Birmingham], Departamento de Física e Astronomia [Porto] (DFA/FCUP), Faculdade de Ciências da Universidade do Porto (FCUP), Universidade do Porto = University of Porto-Universidade do Porto = University of Porto, Danmarks Tekniske Universitet = Technical University of Denmark (DTU), Laboratoire Univers et Particules de Montpellier (LUPM), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), LAboratoire PLasma et Conversion d'Energie (LAPLACE), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT), Institut für Physik, Universität Rostock, Landessternwarte Königstuhl [ZAH] (LSW), Universität Heidelberg [Heidelberg] = Heidelberg University, Mécanismes adaptatifs : des organismes aux communautés (MAOAC), Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Historisches Institut, Universität Paderborn (UPB), Hansen Experimental Physics Lab [Stanford] (HEPL), Stanford University, Konkoly Observatory, Research Centre for Astronomy and Earth Sciences [Budapest], Hungarian Academy of Sciences (MTA)-Hungarian Academy of Sciences (MTA), Department of Experimental Physics, University of Szeged [Szeged], ELTE Gothard Astrophysical Observatory, Eötvös Loránd University (ELTE), Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), 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), Juelich Centre for Neutron Science, IFF, Forschungszentrum Juelich, Institut fuer Festkoerperforschung Juelich, Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Universität Bern [Bern], Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Université de Genève (UNIGE), Laboratoire d'astrophysique de l'observatoire de Besançon (LAOB), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Université Grenoble Alpes (UGA), University of California-University of California, Universidade do Porto [Porto], Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), European Space Agency (ESA)-European Space Agency (ESA), Tel Aviv University [Tel Aviv], Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), The Open University [Milton Keynes] (OU), Max-Planck-Institut für Sonnensystemforschung (MPS), Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Osaka City University Advanced Mathematical Institute (OCAMI), Osaka Media Center, Technical University of Denmark [Lyngby] (DTU), Université de Montpellier (UM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Universität Heidelberg [Heidelberg], Muséum national d'Histoire naturelle (MNHN)-Collège de France (CdF)-Centre National de la Recherche Scientifique (CNRS), Hansen Experimental Physics Laboratory (HEPL), Stanford University [Stanford], ELTE Gao-Lendulet Research Group, Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Low Energy Astrophysics (API, FNWI), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Universidade do Porto, Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Osaka City university Advanced Mathematical Institute [Osaka] (OCAMI), Osaka City University (OCU), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Montpellier 2 - Sciences et Techniques (UM2), 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), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), and Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)

Subjects
photometry, Gas giant, 530 Physics, FOS: Physical sciences, asteroseismology, Astrophysics::Cosmology and Extragalactic Astrophysics, transit surey, Asteroseismology, INSTRUMENTAÇÃO (ASTRONOMIA), Planet, Astrophysics::Solar and Stellar Astrophysics, ComputingMilieux_MISCELLANEOUS, Astrophysics::Galaxy Astrophysics, Physics, Earth and Planetary Astrophysics (astro-ph.EP), Seismaology, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Exoplanetary science, Planetary habitability, Exoplanets, 520 Astronomy, Stellar science, Astronomy, Astronomy and Astrophysics, Planetary system, 620 Engineering, Exoplanet, Stars, exoplanets, 13. Climate action, Space and Planetary Science, Transit survey, Terrestrial planet, Astrophysics::Earth and Planetary Astrophysics, Circumstellar habitable zone, Astrophysics - Earth and Planetary Astrophysics
Abstract

PLATO 2.0 has recently been selected for ESA's M3 launch opportunity (2022/24). Providing accurate key planet parameters (radius, mass, density and age) in statistical numbers, it addresses fundamental questions such as: How do planetary systems form and evolve? Are there other systems with planets like ours, including potentially habitable planets? The PLATO 2.0 instrument consists of 34 small aperture telescopes (32 with 25 sec readout cadence and 2 with 2.5 sec candence) providing a wide field-of-view (2232 deg2) and a large photometric magnitude range (4-16 mag). It focusses on bright (4-11 mag) stars in wide fields to detect and characterize planets down to Earth-size by photometric transits, whose masses can then be determined by ground-based radial-velocity follow-up measurements. Asteroseismology will be performed for these bright stars to obtain highly accurate stellar parameters, including masses and ages. The combination of bright targets and asteroseismology results in high accuracy for the bulk planet parameters: 2%, 4-10% and 10% for planet radii, masses and ages, respectively. The planned baseline observing strategy includes two long pointings (2-3 years) to detect and bulk characterize planets reaching into the habitable zone (HZ) of solar-like stars and an additional step-and-stare phase to cover in total about 50% of the sky. PLATO 2.0 will observe up to 1,000,000 stars and detect and characterize hundreds of small planets, and thousands of planets in the Neptune to gas giant regime out to the HZ. It will therefore provide the first large-scale catalogue of bulk characterized planets with accurate radii, masses, mean densities and ages. This catalogue will include terrestrial planets at intermediate orbital distances, where surface temperatures are moderate. Coverage of this parameter range with statistical numbers of bulk characterized planets is unique to PLATO 2.0., Comment: 63 pages, 17 figures, submitted to Experimental Astronomy (ExA)

Published
2014

5. A large sample of calibration stars for Gaia: log g from Kepler and CoRoT

Author

Creevey, O. L., Thévenin, F., Basu, S., Chaplin, W. J., Bigot, L., Elsworth, Y., Huber, D., Monteiro, M. J. P. F. G., and Serenelli, A.

Subjects
Astrophysics - Solar and Stellar Astrophysics, Astrophysics of Galaxies (astro-ph.GA), FOS: Physical sciences, Astrophysics - Astrophysics of Galaxies, Solar and Stellar Astrophysics (astro-ph.SR)
Abstract

Asteroseismic data can be used to determine surface gravities with precisions of < 0.05 dex by using the global seismic quantities Deltanu and nu_max along with Teff and [Fe/H]. Surface gravity is also one of the four stellar properties to be derived by automatic analyses for 1 billion stars from Gaia data (workpackage GSP_Phot). We explore seismic data from MS F, G, K stars (solar-like stars) observed by Kepler as a potential calibration source for methods that Gaia will use for object characterisation (log g). We calculate log g for bright nearby stars for which radii and masses are known, and using their global seismic quantities in a grid-based method, we determine an asteroseismic log g to within 0.01 dex of the direct calculation, thus validating the accuracy of our method. We find that errors in Teff and mainly [Fe/H] can cause systematic errors of 0.02 dex. We then apply our method to a list of 40 stars to deliver precise values of surface gravity, i.e. sigma < 0.02 dex, and we find agreement with recent literature values. Finally, we explore the precision we expect in a sample of 400+ Kepler stars which have their global seismic quantities measured. We find a mean uncertainty (precision) on the order of, Accepted MNRAS, 15 pages (10 figures and 3 tables), v2=some rewording of two sentences

Published
2013
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6. Successful Asteroseismology for a Better Characterization of the Exoplanet HAT-P-7b

Author

Oshagh, M., Grigahcène, A., Benomar, O., Dupret, M. -A., Monteiro, M. J. P. F. G., Scuflaire, R., and Santos, N. C.

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), Astrophysics - Solar and Stellar Astrophysics, Astrophysics::Solar and Stellar Astrophysics, FOS: Physical sciences, Astrophysics::Earth and Planetary Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics - Earth and Planetary Astrophysics
Abstract

It is well known that asteroseismology is the unique technique permitting the study of the internal structure of pulsating stars using their pulsational frequencies, which is per se very important. It acquires an additional value when the star turns out to be a planet host. In this case, the asteroseismic study output may be a very important input for the study of the planetary system. With this in mind, we use the large time-span of the Kepler public data obtained for the star system HAT-P-7, first to perform an asteroseismic study of the pulsating star using Time-Dependent-Convection (TDC) models. Secondly, we make a revision of the planet properties in the light of the asteroseismic study., Comment: 4 pages, 2 figures, Published in the Stellar Pulsations, Astrophysics and Space Science Proceedings, Volume 31., p. 227, 2013

Published
2013
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7. On the possibility of using seismic probes to study the core composition in pulsating white dwarfs

Author

Faria, J. P. and Monteiro, M. J. P. F. G.

Subjects
Astrophysics - Solar and Stellar Astrophysics, FOS: Physical sciences, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics
Abstract

White dwarfs correspond to the final stages of stellar evolution of solar-type stars. In these objects, production of energy by nuclear burning has ended which means that a white dwarf simply cools down over the course of the next billion years. It is now known that white dwarfs spend some of their cooling history in an instability strip. The pulsating white dwarfs with an hydrogen atmosphere (called DAV or ZZ Ceti stars) show non-radial oscillation modes with periods in the range 100 - 1200s. In this work we try to illustrate how the oscillation p-mode frequencies of idealized white dwarf models change as the result of a different chemical composition in the core, with the ultimate goal of determining the chemical stratification from seismic observations. The presence of acoustic glitches in the internal structure results in a periodic signal in the frequencies. We find that this signal depends on the chemical stratification/composition of the core in a form that can be analytically modelled., 4 pages, 4 figures, The Modern Era of Helio- and Asteroseismology, to be published in Astron. Nachr. 333, No. 10, 954 - 957 (2012)

Published
2012

8. Towards precise asteroseismology of solar-like stars

Author

Grigahc��ne, A., Dupret, M. -A., Sousa, S. G., Monteiro, M. J. P. F. G., Garrido, R., Scuflaire, R., and Gabriel, M.

Subjects
Astrophysics - Solar and Stellar Astrophysics, FOS: Physical sciences, Solar and Stellar Astrophysics (astro-ph.SR)
Abstract

Adiabatic modeling of solar-like oscillations cannot exceed a certain level of precision for fitting individual frequencies. This is known as the problem of near surface effects on the mode physics. We present a theoretical study which addresses the problem of frequency precision in non-adiabatic models using a time-dependent convection treatment. We find that the number of acceptable model solutions is significantly reduced and more precise constraints can be imposed on the models. Results obtained for a specific star (beta Hydri) lead to very good agreement with both global and local seismic observables. This indicates that the accuracy of model fitting to seismic data is greatly improved when a more complete description of the interaction between convection and pulsation is taken into account., 4 pages, 2 figures. To be published in Astrophysics and Space Science Proceedings series (ASSP). Proceedings of the "20th Stellar Pulsation Conference Series: Impact of new instrumentation and new insights in stellar pulsations", 5-9 September 2011, Granada, Spain

Published
2011

9. Preparation of Kepler lightcurves for asteroseismic analyses

Author

Garcia, R. A., Hekker, S., Stello, D., Gutierrez-Soto, J., Handberg, R., Huber, D., Karoff, C., Uytterhoeven, K., Appourchaux, T., Chaplin, W. J., Elsworth, Y., Mathur, S., Ballot, J., Christensen-Dalsgaard, J., Gilliland, R. L., Houdek, G., Jenkins, J. M., Kjeldsen, H., McCauliff, S., Metcalfe, T., Middour, C. K., Molenda-Zakowicz, J., Monteiro, M. J. P. F. G., Smith, J. C., and Thompson, M. J.

Subjects
Astrophysics - Solar and Stellar Astrophysics, Astrophysics::Instrumentation and Methods for Astrophysics, Astrophysics::Solar and Stellar Astrophysics, FOS: Physical sciences, Astrophysics::Earth and Planetary Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR)
Abstract

The Kepler mission is providing photometric data of exquisite quality for the asteroseismic study of different classes of pulsating stars. These analyses place particular demands on the pre-processing of the data, over a range of timescales from minutes to months. Here, we describe processing procedures developed by the Kepler Asteroseismic Science Consortium (KASC) to prepare light curves that are optimized for the asteroseismic study of solar-like oscillating stars in which outliers, jumps and drifts are corrected., Comment: Accepted for publication in MNRAS. 5 pages, 2 figures

Published
2011
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10. Atmospheric parameters and pulsational properties for a sample of $��$\,Sct, $��$\,Dor, and hybrid {\it Kepler} targets

Author

Catanzaro, G., Ripepi, V., Bernabei, S., Marconi, M., Balona, L., Kurtz, D. W., Smalley, B., Borucki, W. J., Bruntt, H., Christensen-Dalsgaard, J., Grigahcene, A., Kjeldsen, H., Koch, D. G., Monteiro, M. J. P. F. G., Suarez, J. C., Szabo, R., and Uytterhoeven, K.

Subjects
Astrophysics::Solar and Stellar Astrophysics, FOS: Physical sciences, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR)
Abstract

We report spectroscopic observations for 19 $��$\,Sct candidates observed by the {\it Kepler} satellite both in long and short cadence mode. For all these stars, by using spectral synthesis, we derive the effective temperature, the surface gravity and the projected rotational velocity. An equivalent spectral type classification has been also performed for all stars in the sample. These determinations are fundamental for modelling the frequency spectra that will be extracted from the {\it Kepler} data for asteroseismic inference. For all the 19 stars, we present also periodograms obtained from {\it Kepler} data. We find that all stars show peaks in both low- ($��$\,Dor; g mode) and high-frequency ($��$\,Sct; p mode) regions. Using the amplitudes and considering 5\,c/d as a boundary frequency, we classified 3 stars as pure $��$\,Dor, 4 as $��$\,Dor\,-\,$��$\ hybrid, Sct, 5 as $��$\,Sct\,-\,$��$\,Dor hybrid, and 6 as pure $��$\,Sct. The only exception is the star KIC\,05296877 which we suggest could be a binary., 11 pages, 6 figures, MNRAS main journal

Published
2010
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11. Might intermediate-order g modes observed in the CoRoT hybrid gamma Doradus/delta Scuti star HD 49434 be stochastically excited?

Author

Campante, T. L., Grigahcène, A., Suárez, J. C., and Monteiro, M. J. P. F. G.

Subjects
Astrophysics - Solar and Stellar Astrophysics, Astrophysics::Solar and Stellar Astrophysics, FOS: Physical sciences, Astrophysics - Instrumentation and Methods for Astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), Solar and Stellar Astrophysics (astro-ph.SR)
Abstract

The primary target in the seismo-field of CoRoT, HD 49434, known to be a bona fide hybrid gamma Doradus/delta Scuti, shows excited intermediate-order g modes. Time-Dependent Convection models, however, predict a range in frequency that is stable to pulsations, between the simultaneously excited high-order g modes (gamma Dor) and low-order p and g modes (delta Sct). Furthermore, theoretical studies based on model computations of delta Sct stars suggest that stochastically excited modes are likely to be observed. A pertinent question would then be to ask: Might those observed intermediate-order g modes be stochastically excited? By employing a statistical method which searches for the signature of stochastic excitation in stellar pulsations, we investigate the nature of those modes with possible implications on the identification of their excitation mechanism. Preliminary results are rather inconclusive about the presence of stochastic excitation. A new analysis that thoroughly takes into account sampling effects is necessary in order to get more reliable results., Comment: 4 pages, 3 figures, submitted to Astronomische Nachrichten, to appear in the proceedings of the IV HELAS International Conference

Published
2010
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12. Asteroseismology across the HR diagram

Author

Monteiro, M. J. P. F. G.

Subjects
Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics
Abstract

High precision spectroscopy provides essential information necessary to fully exploit the opportunity of probing the internal structure of stars using Asteroseismology. In this work we discuss how Asteroseismology combined with High Precision Spectroscopy can establish a detailed view on stellar structure and evolution of stars across the HR diagramme., 6 pages, 2 figures - to appear in Precision Spectroscopy in Astrophysics, (Eds) L. Pasquini, M. Romaniello, N.C. Santos, and A. Correia, ESO Astrophysics Symposia, 2007

Published
2007

13. Report on the CoRoT Evolution and Seismic Tools Activity

Author

Monteiro, M. J. P. F. G., Lebreton, Y., Montalbán, J., Jorgen Christensen-Dalsgaard, Castro, M., Degl Innocenti, S., Moya, A., Roxburgh, I. W., Scuflaire, R., Baglin, A., Cunha, M. S., Eggenberger, P., Fernandes, J., Goupil, M. J., Hui-Bon-Hoa, A., Marconi, M., Marques, J. P., Michel, E., Miglio, A., Morel, P., Pichon, B., Prada Moroni, P. G., Provost, J., Ruoppo, A., C Suárez, J., Suran, M., Teixeira, T. C., 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 d'Astrophysique et de Géophysique [Liège], Université de Liège, Observatoire de Haute-Provence (OHP), Institut Pythéas (OSU PYTHEAS), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut de Recherche pour le Développement (IRD), Laboratoire d'Astrophysique de l'Observatoire Midi-Pyrénées (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), Institut Cavanilles de Biodiversitat i Biologia Evolutiva (ICBiBE), Universitat de València (UV), 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 Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), Centre de recherche du CHUM (CR), CHUM-Hôpital Notre-Dame, Laboratoire Astrophysique de Toulouse-Tarbes (LATT), Centre National de la Recherche Scientifique (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)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, 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), PSL Research University (PSL)-PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Friedlund, M., Baglin, A., Lochard, J., Conroy, L., Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-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), 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), Université de Genève = University of Geneva (UNIGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics
Abstract

We present the work undertaken by the Evolution and Seismic Tools Activity (ESTA) team of the CoRoT Seismology Working Group. We have focused on two main tasks: Task 1 - now finished - has aimed at testing, comparing and optimising seven stellar evolution codes which will be used to model the internal structure and evolution of the CoRoT target stars. Task 2, still underway, aims at testing, comparing and optimising different seismic codes used to calculate the oscillations of models for different types of stars. The results already obtained are quite satisfactory, showing minor differences between the different numerical tools provided the same assumptions on the physical parameters are made. This work gives us confidence on the numerical tools that will be available to interpret the future CoRoT seismic data., To appear in: "The CoRoT Book", (Eds) F. Favata, A. Baglin & J. Lochard, ESA Publications Division, ESA SP

Published
2006

14. Discovery of $��$ Scuti pulsation in the Herbig Ae star VV Ser

Author

Ripepi, V., Bernabei, S., Marconi, M., Ruoppo, A., Palla, F., Monteiro, M. J. P. F. G., Marques, J. P., Ferrara, P., Marinoni, S., and Terranegra, L.

Subjects
Astrophysics (astro-ph), Astrophysics::Solar and Stellar Astrophysics, FOS: Physical sciences, Astrophysics::Earth and Planetary Astrophysics
Abstract

A new observational study of the Herbig Ae star VV Ser has been performed in order to detect and accurately measure pulsation frequencies in the $��$ Scuti range. As it belongs to the continuous field of view of the asteroseismological satellite COROT, this study also aims at characterizing the properties of VV Ser as a potential ``COROT additional program'' candidate. CCD time series photometry in the Johnson V filter has been obtained during three consecutive years. The resulting light curves have been subject to detailed frequency analysis and the derived frequencies have been compared to model predictions. Seven pulsation frequencies have been measured on the basis of the best dataset obtained in 2004, ranging from $\sim$ 31 to $\sim$ 118 $��Hz$, with an accuracy of the order of 0.5 $��Hz$. The comparison with an extensive set of asteroseismological models shows that all the observed periodicities can be reproduced if the stellar mass is close to $4 M_{\odot}$. Conversely, the measured frequencies can be associated to $p$ modes only if the effective temperature is significantly lower than that obtained from the spectral type conversion. The present results seem to suggest that more accurate spectral type determination is necessary in order to discriminate the best fit model solution. In any case, the stellar mass of VV Ser is close to the upper mass limit ($\sim 4 M_{\odot}$) for this class of pulsators., A&A Accepted, 10 pages + 4 pages online material

Published
2006
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15. On the effect of overshooting as predicted by the modelling of the pre-main sequence evolution of a 2 solar-mass star

Author

Marques, J. P., Monteiro, M. J. P. F. G., and Fernandes, J.

Subjects
Astrophysics (astro-ph), Astrophysics::Solar and Stellar Astrophysics, FOS: Physical sciences, Astrophysics, Physics::Atmospheric and Oceanic Physics, Astrophysics::Galaxy Astrophysics
Abstract

We discuss the effects of convective overshooting in the PMS evolution of intermediate mass stars, by analysing in detail the early evolution towards the main sequence of a 2 M_sun stellar model. These effects can be extremely important in the end of the PMS, when the abundances in CNO elements approach the equilibrium in the centre. We provide a possible physical explanation on why a moderate amount of overshooting produces, as the star approaches the ZAMS, an extra loop in the evolutionary tracks on the HR diagram. An interesting feature is that there is a very well defined amount of overshooting (for a given stellar mass and chemical composition) beyond which a loop is produced. For smaller amounts of overshooting such a loop does not take place and the evolutionary tracks are similar to the ones obtained by Iben (1965). The amount of overshooting needed to produce the loop decreases with stellar mass. We discuss the underlining physical reasons for the behaviour predicted by the evolution models and argue that it provides a crucial observational test for convective overshooting in the core of intermediate mass stars., Comment: 10 pages and 7 figures - to appear in MNRAS

Published
2006
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16. A multisite photometric campaign on the Pre-Main-Sequence delta Scuti pulsator IP Per

Author

Ripepi, V., Bernabei, S., Marconi, M., Palla, F., Ferro, A. Arellano, Bonanno, A., Ferrara, P., Frasca, A., Jiang, X. J., Kim, S. -L., Marinoni, S., Mignemi, G., Monteiro, M. J. P. F. G., Oswalt, T. D., Reegen, P., Janulis, R., Rodriguez, E., Rolland, A., Ruoppo, A., Terranegra, L., and Zwintz, K.

Subjects
Astrophysics::High Energy Astrophysical Phenomena, Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics
Abstract

We present the results of a photometric multisite campaign on the $\delta$ Scuti Pre-Main-Sequence star IP Per. Nine telescopes have been involved in the observations, with a total of about 190 hours of observations over 38 nights. Present data confirms the multiperiodic nature of this star and leads to the identification of at least nine pulsational frequencies. Comparison with the predictions of linear non-adiabatic radial pulsation models allowed us to identify only five of the nine observed frequencies, and to constrain the position of IP Per in the HR diagram. The latter is in good agreement with the empirical determination of the stellar parameters obtained by Miroshnichenko et al. (2001). An initial interpretation of the observed frequencies using the Aarhus non-radial pulsation code suggests that three frequencies could be associated with non-radial ($l$=2) modes. Finally, we present new evolutionary and pulsation models at lower metallicity (Z=0.008) to take into account the possibility that IP Per is metal deficient, as indicated by Miroshnichenko et al. (2001)., Comment: 10 pages 11 figures, accepted for publication on A&A

Published
2005

17. Kepler White Paper: Asteroseismology of Solar-Like Oscillators in a 2-Wheel Mission

Author

Chaplin, W. J., Kjeldsen, H., Christensen-Dalsgaard, J., Gilliland, R. L., Kawaler, S. D., Basu, S., Ridder, J., Huber, D., Arentoft, T., Schou, J., Garcia, R. A., Metcalfe, T. S., Karsten Brogaard, Campante, T. L., Elsworth, Y., Miglio, A., Appourchaux, T., Bedding, T. R., Hekker, S., Houdek, G., Karoff, C., Molenda-Zakowicz, J., Monteiro, M. J. P. F. G., Silva Aguirre, V., Stello, D., Ball, W., Beck, P. G., Birch, A. C., Buzasi, D. L., Casagrande, L., Cellier, T., Corsaro, E., Creevey, O. L., Davies, G. R., Deheuvels, S., Dogan, G., Gizon, L., Grundahl, F., Guzik, J., Handberg, R., Jimenez, A., Kallinger, T., Lund, M. N., Lundkvist, M., Mathis, S., Mathur, S., Mazumdar, A., Mosser, B., Neiner, C., Nielsen, M. B., Palle, P. L., Pinsonneault, M. H., Salabert, D., Serenelli, A. M., Shunker, H., and White, T. R.

Subjects
Astrophysics - Solar and Stellar Astrophysics, FOS: Physical sciences, Solar and Stellar Astrophysics (astro-ph.SR)
Abstract

We comment on the potential for continuing asteroseismology of solar-type and red-giant stars in a 2-wheel Kepler Mission. Our main conclusion is that by targeting stars in the ecliptic it should be possible to perform high-quality asteroseismology, as long as favorable scenarios for 2-wheel pointing performance are met. Targeting the ecliptic would potentially facilitate unique science that was not possible in the nominal Mission, notably from the study of clusters that are significantly brighter than those in the Kepler field. Our conclusions are based on predictions of 2-wheel observations made by a space photometry simulator, with information provided by the Kepler Project used as input to describe the degraded pointing scenarios. We find that elevated levels of frequency-dependent noise, consistent with the above scenarios, would have a significant negative impact on our ability to continue asteroseismic studies of solar-like oscillators in the Kepler field. However, the situation may be much more optimistic for observations in the ecliptic, provided that pointing resets of the spacecraft during regular desaturations of the two functioning reaction wheels are accurate at the < 1 arcsec level. This would make it possible to apply a post-hoc analysis that would recover most of the lost photometric precision. Without this post-hoc correction---and the accurate re-pointing it requires---the performance would probably be as poor as in the Kepler-field case. Critical to our conclusions for both fields is the assumed level of pointing noise (in the short-term jitter and the longer-term drift). We suggest that further tests will be needed to clarify our results once more detail and data on the expected pointing performance becomes available, and we offer our assistance in this work., NASA Kepler Mission White Paper; 10 pages, 2 figures

18. Seismic Analysis of Four Solar-like Stars Observed during More Than Eight Months by Kepler

Author

Mathur, S., Campante, T. L., Rasmus Handberg, Garcia, R. A., Appourchaux, T., Bedding, T. R., Mosser, B., Chaplin, W. J., Ballot, J., Benomar, O., Bonanno, A., Corsaro, E., Gaulme, P., Hekker, S., Regulo, C., Salabert, D., Verner, G., White, T. R., Brandao, I. M., Creevey, O. L., Dogan, G., Bazot, M., Cunha, M. S., Elsworth, Y., Huber, D., Hale, S. J., Günter Houdek, Christoffer Karoff, Mia Lundkvist, Metcalfe, T. S., Molenda-Zakowicz, J., Monteiro, M. J. P. F. G., Thompson, M. J., Stello, D., Jorgen Christensen-Dalsgaard, Gilliland, R. L., Kawaler, S. D., Kjeldsen, H., Clarke, B. D., Girouard, F. R., Hall, J. R., Quintana, E. V., Sanderfer, D. T., and Seader, S. E.

Subjects
Astrophysics - Solar and Stellar Astrophysics, FOS: Physical sciences, Solar and Stellar Astrophysics (astro-ph.SR)
Abstract

Having started science operations in May 2009, the Kepler photometer has been able to provide exquisite data of solar-like stars. Five out of the 42 stars observed continuously during the survey phase show evidence of oscillations, even though they are rather faint (magnitudes from 10.5 to 12). In this paper, we present an overview of the results of the seismic analysis of 4 of these stars observed during more than eight months., 5 pages, 1 figure. To appear in the ASP proceedings of "The 61st Fujihara seminar: Progress in solar/stellar physics with helio- and asteroseismology", 13th-17th March 2011, Hakone, Japan

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