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Imagerie Des Exoplanètes : Du Système Optique À La Fréquence Des Géantes Gazeuses Raphaël Galicher

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Imagerie Des Exoplanètes : Du Système Optique À La Fréquence Des Géantes Gazeuses Raphaël Galicher Imagerie des exoplanètes : du système optique à la fréquence des géantes gazeuses Raphaël Galicher To cite this version: Raphaël Galicher. Imagerie des exoplanètes : du système optique à la fréquence des géantes gazeuses. Instrumentation et méthodes pour l’astrophysique [astro-ph.IM]. Observatoire de Paris, 2020. tel- 03102022 HAL Id: tel-03102022 https://tel.archives-ouvertes.fr/tel-03102022 Submitted on 7 Jan 2021 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. Unit´ede formation et d'Enseignement Imagerie des exoplan`etes: du syst`emeoptique `ala fr´equencedes g´eantes gazeuses pr´esent´eeet soutenue publiquement le 18 d´ecembre 2020 pour l'obtention d'une Habilitation `adiriger des recherches par Rapha¨elGalicher Composition du jury Pr´esident: Daniel Rouan Observatoire de Paris-PSL Rapporteurs : Magali Deleuil Universit´eAix-Marseille Dimitri Mawet California institute of technology R´emiSoummer Space telescope science institute Examinateurs : Marc Ferrari Universit´eAix-Marseille Anne-Marie Lagrange Universit´eGrenoble Alpes Laboratoire d'Etudes´ Spatiales et d'Instrumentation en Astrophysique | UMR 8109 Mis en page avec la classe thloria. Remerciements Paragraphe compliqué à écrire que celui des remerciements. Non pas que j’ai du mal à re- mercier mais parce qu’à l’aube de mes quarante ans, je suis sûr d’oublier certaines personnes qui font que j’écris ce document. Un livre ne suffirait pas à lister les raisons pour lesquelles je les remercies alors je me contente d’une seule phrase : merci du fond du cœur à mes parents qui m’ont appris à être curieux, à chercher à comprendre et, quand j’y arrive, à m’adapter à la situation. Ce sont trois forces essentielles quand on exerce le métier d’enseignant-chercheur. Un grand merci à Pierre-Marie, Jean-Baptiste et Antoine-Laurent qui, me croisant au hasard d’un couloir du lycée Masséna à Nice, m’ont suggéré de venir faire une prépa avec eux plutôt que des études de STAPS. Je me serais certainement épanoui en tant que professeur d’EPS mais le sort en a décidé autrement. Je remercie toutes les personnes que j’ai eu la chance de rencontrer depuis mon premier pas dans le monde de l’astronomie professionnelle en 2002, à l’Observatoire de la Côte d’Azur, dans les observatoires hawaiiens, en Île-de-France pendant le master, à l’institut d’astrophysique Herzberg, au VLT, sur le mont Palomar, dans les consortia GPI et Sphere, etc. Échanger avec des collègues aux quatre coins de la planète est une véritable richesse. Et ils ont tous influencé à leur manière ce manuscrit. Depuis que j’ai gravi la côte de Meudon pour la première fois en 2005 (en rollers s’il-vous- plaît), mon chemin a croisé à l’Observatoire de Paris celui de plusieurs belles personnes qui m’ont offert des bouts d’elles tant sur le plan scientifique qu’humain. Il y a les enseignants et les amis du M2 A&A de 2005, les collègues des DU ECU/SU, ceux qui ont partagé les missions au Bénin et au Gabon, et les administratifs dont le travail, indispensable à nos projets de recherche, est souvent oublié. Merci à vous tous ! Je remercie spécialement l’équipe très haute dynamique du Lesia avec qui j’ai la chance de pouvoir travailler sérieusement, rigoureusement et, dans la bonne humeur. C’est un plaisir de mener des études à vos côtés. Merci à Elsa, Anthony, Johan, Olivier, Simone, tous les ingénieurs, et tous les étudiants qui travaillent avec nous, de la licence à la thèse en passant par les écoles ingénieurs et les apprentis. Enfin, le mot merci est trop petit pour exprimer ma reconnaissance envers Pierre. Déjà quinze ans que nous nous sommes rencontrés pour la première fois. J’ai l’impression que c’était hier. Travailler à ses côtés et discuter de tout et de rien avec lui m’enrichit chaque jour un peu plus. Pierre, merci pour tout ! i ii À mes parents, à ma soeur, iii iv Table des matières Partie I Curriculum vitæ 1 Partie II Dossier de synthèse 1 Contexte 11 1.1 Exoplanètes . 11 1.1.1 Diversité . 11 1.1.2 Techniques de détection . 11 1.1.3 Que cherche-t-on à comprendre ? . 12 1.1.3.1 Formation planétaire . 12 1.1.3.2 Atmosphère exoplanétaire . 13 1.1.3.3 Vie extraterrestre . 14 1.2 Imagerie haute dynamique . 15 1.2.1 Pourquoi l’imagerie ? . 15 1.2.2 Une luciole près d’un phare maritime . 15 1.3 Instruments coronographiques en 2020 . 16 1.3.1 Coronographe . 16 1.3.2 Coronographes et aberrations . 16 v Table des matières 1.3.3 Aberrations turbulentes et quasi-statiques . 17 1.3.4 Optique adaptative . 18 1.3.5 Imagerie différentielle . 18 1.3.6 Quelle performance ? . 20 2 L’imagerie d’exoplanètes de demain 21 2.1 Un type d’instrument par objectif scientifique . 21 2.1.1 Caractérisation spectrale fine . 21 2.1.2 Nouvelles détections et caractérisations . 22 2.2 Instruments coronographiques de demain au sol . 22 2.2.1 Coupler deux boucles d’asservissement . 22 2.2.2 Analyseur de surface d’onde en plan focal . 23 2.2.3 Minimisation en plan focal vs optique adaptative . 24 2.2.4 Imagerie différentielle et télémétrie . 25 2.2.5 Coronographes . 25 2.3 Instrument coronographique de demain dans l’espace . 26 3 Projet de recherche 27 3.1 Astrophysique . 27 3.1.1 Fréquence des planètes géantes gazeuses . 27 3.1.2 Études d’objets de masse planétaire . 28 3.1.2.1 Fomalhaut b : une exoplanète ou autre chose ? . 28 3.1.2.2 HR 8799 en bande M . 28 3.1.2.3 HD 95086 . 28 3.1.3 Outil SpeCal pour le consortium Sphere . 29 3.2 Instrumentation . 30 3.2.1 Le banc très haute dynamique . 30 3.2.1.1 Le banc THD . 30 3.2.1.2 Le banc THD2 . 31 3.2.2 Mise en œuvre à Palomar et sur Sphere . 33 3.2.2.1 Self-coherent Camera sur le SDC à Palomar . 34 3.2.2.2 Pair wise/EFC sur Sphere au VLT . 35 3.3 Projets . 36 vi Partie III Note d’accompagnement 1 Encadrement d’étudiants et de jeunes chercheurs 39 1.1 Lucie Leboulleux (post-doc) : Coherence differential imaging . 39 1.2 Garima Singh (post-doc) : Sphere+ et PCS/ELT . 39 1.3 Tobias Schmidt (post-doc) : Astro-photométrie avec Sphere . 39 1.4 Fabien Patru (post-doc) : coronographie en large bande . 40 1.5 J.-R. Delorme (master 2 et thèse) : analyse de surface d’onde en large bande 40 1.6 Axel Potier (thèse) : analyse et contrôle de surface d’onde . 40 1.7 Ben Gerard (thèse) : coronographie et imagerie différentielle . 40 1.8 Coline Lopez (Master 2) : coronographie en large bande . 41 1.9 Tristan Madeleine (Master 1) : fréquence des exoplanètes . 41 1.10 Mona El Morsi (Master 1) : modulation temporelle d’images coronographiques 41 1.11 Sofiane Meziani (Master 1) : coronographie stellaire . 42 1.12 Yusuke Komuro (Master 1) : coronographe à huit octants . 42 1.13 Andréa Capomassi et Benjamin Steir (ingénieurs) : simulation optique d’une OA 42 1.14 Zineb Bouharras (ingénieur) : masque de phase polarisant . 42 2 Répartition du temps de travail 43 Annexes 1 Galicher et al., 2016, AA, 594, A63 47 2 Galicher et al., 2011, ApJL, 739, L41 63 3 Galicher et al., 2014, AA, 565, L4 69 4 Galicher et al., 2018, AA, 615, A92 75 vii Table des matières 5 Delorme et al., 2016 ; AA, 588, A136.pdf 87 Table des figures 103 Liste des tableaux 105 Bibliographie 107 viii Première partie Curriculum vitæ 1 RaphaëlGalicher Born on 1981, no children, Associate Professor (Maître de Conférences) University of Paris, LESIA, UMR8109 Research Responsabilities Since 2020 SPHERE+/VLT, co-I, upgrade of the SPHERE+ instrument for exoplanet imaging. Since 2012 THD2 bench, co-PI ( 10 persons), laboratory R&D for high contrast imaging, compar- ∼ ing, associating and optimizing very high contrast imaging techniques for the exoplanet imagers of future telescopes (space, balloon, and ground). 2012 – 2016 Sphere/VLT pipeline, co-leader, development of the automatic pipeline to reduce all IRDIS/IFS data of the SPHERE 5 year survey: astrometry, spectro-photometry of exoplanets. Instrumentation Since 2010 Broadband coronagraphy, development of broadband phase and amplitude masks. Since 2006 Wavefront control high contrast imaging, from lab to current instruments like SPHERE. 2013 – 2016 Broadband wavefront sensing, development of a focal plane wavefront sensor. 2010 – 2012 Gemini Planet imager, detector linearity, wavefront control for coronagraphy. 2009 – 2010 Spices mission, optical design and science cases for a mission proposed to ESA. Astrophysics Since 2014 Exoplanetary systems, astrometry and spectro-photometry of giant exoplanets and brown dwarfs orbiting HR 8799, Fomalhaut, HD 95086, etc ; and disk imaging. 2012 – 2018 Occurrence of giant exoplanets, 14-year survey (Keck, Gemini Nord et Sud, HST, VLT) to determine the giant planet frequency. Teaching: courses Responsabilities Since 2019 Mechanics, optics, electronics, Licence 1, lecture, lab, 190 students/year. ∼ Since 2014 Optics, Engineering School 1st year, lecture, tutorial, lab, 20 students/year. ∼ 2014 – 2019 Wave and vibration, Licence 2, lab, 150 students/year.
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