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Sismologie Solaire Et Stellaire Pascal Lambert Sismologie solaire et stellaire Pascal Lambert To cite this version: Pascal Lambert. Sismologie solaire et stellaire. Astrophysique [astro-ph]. Université Paris-Diderot - Paris VII, 2007. Français. tel-00140766v3 HAL Id: tel-00140766 https://tel.archives-ouvertes.fr/tel-00140766v3 Submitted on 7 Dec 2009 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. École Doctorale d’Astronomie et d’Astrophysique d’Ile-de-France Universite´ Paris VII - Denis Diderot These` de Doctorat présentée pour obtenir le grade de Docteur de l’Université Paris VII - Denis Diderot Spécialité : Astrophysique et Méthodes Associées par Pascal Lambert Sismologie solaire et stellaire Thèse dirigée par Sylvaine TURCK-CHIEZE Soutenue publiquement le 21 mars 2007 devant le jury composé de : Pr. Cécile Ferrari ..........................................Présidente du jury Dr. Rafael A. Garc´ia ..................................... CorrespondantCEA Dr. Eric Michel .................................................Examinateur Dr. Pere L. Palle´ .................................................Rapporteur Dr. Sylvie Roques ................................................Rapporteur Dr. Sylvaine Turck-Chieze` .................................Directricedethèse Service d’Astrophysique DAPNIA/DSM/CEA – Saclay iii Résumé Titre : sismologie solaire et stellaire Laboratoire d’accueil : Service d’Astrophysique, DSM/DAPNIA, CEA/Saclay Résumé : La thèse présentée ici se place dans le cadre de la sismologie du Soleil et des étoiles, dans une période de transition entre une bonne connaissance du Soleil grâce à l’héliosismologie et le développe- ment actuel de l’astérosismologie, et, entre une vision statique et une vision dynamique des étoiles. Le but de mon travail a été de participer à cet effort en dépasser la vision statique des intérieurs stellaires et via le développement d’outils d’analyse des données des missions spatiales. Ainsi le modèle solaire standard actuel, la représentation théorique de l’intérieur solaire, présente des limites, mises en avant par une récente révision de ses abondances. Nous montrons que l’écart entre le modèle standard et les observations sismiques est fortement dégradé motivant l’introduction de processus dynamiques dans les modèles. Nous avons aussi entrepris l’introduction d’effets magnétiques dans les couches superficielles pour améliorer la prédiction des fréquences et l’analyse sismique. Les missions spatiales astérosismiques, présentes et futures, permettent d’avoir accès à des informations sur la dynamique des étoiles (rotation, convection, . .). Pour améliorer ces informations contenues dans les spectres d’oscillations, il est néces- saire d’effectuer une bonne identification des modes ainsi qu’une extraction précise de ces paramètres. Nous montrons comment améliorer ceci en développant une analyse du diagramme-échelle basée sur la récente transformée en curvelette. Cette méthode a pu être validées grâce à des simulations ainsi que dans le cadre d’exercices pour la préparation à la mission CoRoT. Nous nous sommes également intéressé à l’étoile Procyon observée par MOST. Mots-clés : astérosismologie - héliosismologie - Soleil - CoRoT - analyse de données - modèle solaire standard - rotation v Abstract Title : solar and stellar seismology Laboratory : Service d’Astrophysique, DSM/DAPNIA, CEA/Saclay Abstract : The thesis presented here takes place within the framework of the seismology of the Sun and stars, in a transition period between the good knowledge of the Sun thanks to the helioseismology and a current development of the asteroseismology, and, between a static and a dynamic vision of stars. The purpose of my work was to participate in this effort to exceed the static vision of the stellar inside and through the development of data analysis tools for space missions. So the current standard solar model, the theoretical representation of the solar interior, presents limits, emphases by a recent revision of its abundances. We show that the discrepancy between the standard model and the seismic observations is strongly degraded, motivating the introduction of dynamic processes in the models. We also introduced magnetic effects in the superficial layers to improve the prediction of the frequencies and the seismic analysis. The asteroseismic present and future space missions allow us to have access to information on the dynamics of stars (rotation, convection, . .). To improve this information, contained in the oscillation spectra, it is necessary to proceed a good identification of the modes as well as an accurate extraction of these parameters. We show how to improve this by developing an analysis of the echelle diagramme based on the recent curvelet transform. This method has been validated thanks to simulations and within the framework of exercises for the preparation for the CoRoT mission. We have also analysed the case of the star Procyon as observed by the MOST mission. Keywords : asteroseismology - helioseismology - Sun - data analysis - standard solar model - rotation A ma grand-mère Remerciements Et voilà ... c’est fini. Merci à toi lecteur qui t’apprête à plonger dans la lecture de ce manuscrit ... et bon courage. Il y a presque 10 ans (ça passe vite quand même ...), à quelques semaines du bac, je n’imaginais même pas me retrouver ainsi à avoir rédiger cette thèse ... Ce qui est sûr c’est que j’y suis alors j’en profite pour remercier toutes celles et tous ceux que j’ai pû cotoyer, rencontrer et qui m’auront supporté tout ce temps. Evidemment, je commencerai par dire un grand merci du fond du cœur à mes parents pour m’avoir toujours soutenu et encouragé dans mes choix, mes décisions et les épreuves rencontrées. Je pense aussi à ma chère petite sœur, ma famille (merci encore) et mes amis les plus proches, chacun se reconnaîtra. Je tiens aussi à remercier Sylvaine Turck-Chièze pour m’avoir permis d’être acceuilli au sein du Service d’Astrophysique, le dynamisme et la motivation dont elle fait preuve pour défendre et soutenir sa science, ses projets, et surtout pour avoir ses encouragements et sa confiance durant les derniers mois de ma thèse. Un grand merci à Sylvie Roques et Pere Pallé qui m’auront fait le plaisir d’être les rapporteurs de cette thèse. Ainsi quà Cécile Ferrari pour avoir accepter de présider mon jury de thèse et Eric Michel pour sa participation à mon jury. Merci à l’ensemble du Service d’Astrophysique pour l’accueil dont j’aurai bénéficié durant ces 3 années (presque 3 ans et demi). Muchas gracias amistosas a Rafael A. García (y Merche) (qui ne pourra pas reprocher d’avoir mal ortographié son nom pour une fois) por su paciencia, su sostén y su disponibilidad (asi como para su talento de gran defensor) durante 3 años. Spezial danke für Herr Doktor Jérôme Ballot que j’aurais eu le plaisir de cotoyer durant 2 ans et qui aura eu l’immense mérite de me supporter (et de m’encourager) durant tout ce temps. Egalement merci à mon officemate Sacha Brun pour ses encouragements et ses discussions toujours passionnées que ce soit sur le Soleil ou la fiabilité de la R25 (Hellboy rules). Un très grand merci (par désordre alphabétique) à Vincent et Philippe (pour m’avoir aidé à plonger dans le grand bain de la vie parisienne), Doris viele Danke für alles, Jean-Luc (qui a tout appris à Pipo Inzaghi), Adam (comme quoi une entente plus que cordiale est possible entre frog & rosbeef), Pascal (avise collègue), Médéric (mais si c’est très bien les Mac), Savita, Delphine, Sandrine (les 2), Ana, Mat- thias, Laurène, Lilia, Pascal et les autres thèsards et post-doc rencontrés pour leur sympathie et amitié, de même que Yael, Fred, Hervé, Marc, Thierry, Phi, Stéphane, Pierre-Alain, Lydie, Roland et Elizabeth pour m’avoir donné l’opportunité de diffuser notre science. Sans oublier le fidèle Toby évidemment. Enfin merci à ceux qui auront rendu beaucoup de choses plus faciles, John, Paul, George & Ringo, Radiohead, Boards of Canada, the Silver Mount Zion, Mark Lanegan, Sufjan Stevens, Sonic Youth, the Super Furry Animals, Grandaddy, Elbow, Portishead, Pink Floyd, Mogwaï, Autechre, Minus Story, Ar- cade Fire, Tricatel and co., Stanley K., Orson W., Steven S., Peter J., Graham, John, Terry, Eric, Terry & Michael . " Quand nous en serons au temps des cerise Et gai rossignol et merle moqueur Seront tous en fête Les belles auront la folie en tête Et les amoureux du soleil au coeur Quand nous en serons au temps des cerises Sifflera le merle moqueur " xi Remarques preliminaires´ : Dans l’ensemble de ce manuscrit, j’utiliserai les unités du Système International, qui n’est pas encore • répandu comme il le devrait dans la communauté. Par commodité, je maintiendra i tout de même l’emploi de certaines unités usuelles : le parsec (1 pc 30.856 1015 m), l’année-lumière (1 a.l. 9.460 1015 m ), ≈ ≈ l’unité astronomique (1 U.A. 1.49 1011 m) et les unités solaires : masse (M 1.980 1030 kg), rayon ≈ ⊙ ≈ (R 6.960 108 m) et luminosité (L 3.826 1026 W). ⊙ ≈ ⊙ ≈ Dans les expressions mathématiques, les grandeurs vectorielles seront en gras, e.g. 3 au lieu de 3 . • −→ xii xiii Table des matières Résumé iii Abstract v Table des figures xviii Liste des tableaux xix I Introduction 1 Introduction générale 3 II Évolution et structure stellaire 13 1 Évolution et structure stellaire 15 1.1 Évolution stellaire : de la nébuleuse primordiale au Soleil ................. 16 1.1.1 La jeunesse d’une étoile .............................. 16 1.1.2 Vie et mort d’un soleil ............................... 16 1.1.3 Au-delà de la séquence principale ......................... 20 1.2 Structure interne des étoiles : théories et modèles ..................... 20 1.2.1 Les équations de la structure interne .......................
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