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Caractérisation Interférométrique De La Relation Brillance De Surface

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Caractérisation Interférométrique De La Relation Brillance De Surface Caractérisation interférométrique de la relation brillance de surface-couleur des binaires à éclipse et étalonnage des échelles de distance dans l’univers Mounir Challouf To cite this version: Mounir Challouf. Caractérisation interférométrique de la relation brillance de surface-couleur des binaires à éclipse et étalonnage des échelles de distance dans l’univers. Autre. Université Nice Sophia Antipolis, 2015. Français. NNT : 2015NICE4023. tel-01199436 HAL Id: tel-01199436 https://tel.archives-ouvertes.fr/tel-01199436 Submitted on 15 Sep 2015 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. THÈSE Pour l’obtention du grade de DOCTEUR EN PHYSIQUE de l’Université Tunis El Manar FACULTÉ DES SCIENCES MATHÉMATIQUES PHYSIQUES ET NATURELLES DE TUNIS DOCTEUR EN SCIENCES DE L’UNIVERS de l’Université Nice-Sophia Antipolis ÉCOLE DOCTORALE SCIENCES FONDAMENTALES & APPLIQUÉES Présentée par Mounir CHALLOUF Caractérisation interférométrique de la relation brillance de surface-couleur des binaires à éclipse et étalonnage des échelles de distance dans l’univers Directeur de thèse : M. Denis Mourard Co-direction : M. Hassen Aroui Soutenue le 28 Mai 2015 devant la Commission d’Examen JURY Mme. Souad CHEKIR LAHMAR Université de Carthage Président du jury M. Pierre KERVELLA Observatoire de Paris Rapporteur M. Moncef DEROUICH Université de Sousse Rapporteur M. Xavier DELFOSSE Université Joseph Fourier, Grenoble Examinateur M. Denis MOURARD Observatoire de la Côte d’Azur Directeur de thèse M. Hassen AROUI Université de Tunis Directeur de thèse M. Nicolas NARDETTO Observatoire de la Côte d’Azur Invité M. Nejmeddine JAÏDANE Université de Tunis El Manar Invité َ َ َ َ َ َ َ َ َ َ َ َََق ََلََََال ََح ََم ََدَ ََّ ََ َََس َي ََرََيك ََ َََََآي َََات َهَََفَت ََع ََرَف ََن َََ َ ََاَََ ََمََ ََاَر َب ََكَََب ََغ َََاف ََلَ َََع ََمَََاَت ََع ََمَ َ َنَ Table des matières Liste des figures 5 Liste des tableaux 7 Résumé 8 Abstract 9 Introduction générale 11 I Les binaires à éclipses et les distances dans l’Univers 15 1 Distances dans l’univers . 16 1.1 Notion de distances . 16 1.2 L’échelle des distances dans l’univers . 18 1.2.1 Indicateurs primaires . 20 1.2.2 Indicateurs secondaires . 22 2 La méthode des binaires à éclipse . 25 2.1 Le projet "Araucaria" et la détermination des distances dans le groupe local 25 2.2 La relation brillance de surface . 27 2.2.1 Notions de la relation BSC . 27 2.2.2 Historique de la relation BSC . 28 3 Objectifs de la thèse . 30 II L’interférométrie optique longue base 33 1 Interférométrie optique . 34 1.1 Historique de l’interférométrie . 34 1.2 Principe de l’interférométrie . 37 1 Table des matières 1.3 Notions fondamentales de l’interférométrie . 39 1.3.1 La turbulence atmosphérique . 39 1.3.2 Techniques de correction de la turbulence atmosphérique . 41 1.4 Les observables interférométriques . 43 1.4.1 Cohérence spatio-temporelle . 44 1.4.2 Fonction de cohérence mutuelle et degré de cohérence complexe 45 1.4.3 Visibilité et phase des franges d’interférence . 49 1.4.4 Exemple d’application de la Visibilité . 51 2 Le Centre de HAute Résolution Angulaire CHARA . 54 3 Les interféromètres dans le monde . 58 3.1 Le Very Large Telescope Interferometer (VLTI) . 58 3.2 Le Sydney University Stellar Interferometer (SUSI) . 59 3.3 Le Navy Prototype Optical Interferometer (NPOI) . 61 3.4 Le Infrared Spatial Interferometer (ISI) . 61 4 Conclusion . 62 III Observations interférométriques dans le visible avec VEGA / CHARA 65 1 Visible spEctroGraph and polArimeter (VEGA) . 66 1.1 Principe de l’instrument VEGA . 66 1.1.1 Table optique d’interface VEGA-CHARA . 66 1.1.2 Le polarimètre . 68 1.1.3 Le spectrographe . 68 1.2 Objectifs scientifiques de VEGA . 69 1.3 La configuration VEGA/3T-4T . 70 2 Observations CHARA/VEGA d’étoiles utilisées de type précoce . 72 2.1 Critère de sélection des étoiles . 72 2.2 L’échantillon d’étoiles . 73 2.3 Méthodologie d’observation et traitement des données . 74 2.3.1 Proposition et préparation des observations . 74 2.3.2 Observations . 80 2.3.3 Des visibilités brutes aux visibilités calibrées . 83 2.3.4 Modèles d’ajustement . 87 2.4 Détermination des diamètres angulaires . 88 2.4.1 Rotateur lent . 88 2.4.2 Rotateur rapide . 91 2 Table des matières 3 Conclusion . 93 IV Étalonnage de la relation brillance de surface-couleur 95 1 Étalonnage de la relation brillance de surface-couleur . 96 1.1 Les différents échantillons d’étoiles utilisés . 96 1.2 Photométrie stellaire . 98 1.2.1 Magnitudes et indices de couleur . 98 1.2.2 Le rougissement et l’extinction interstellaire . 98 1.2.3 Correction photométrique de la magnitude . 99 2 Relation empirique SV vs (V-K)0 .......................... 103 2.1 Dépendance de la classe spectrale . 103 2.2 Étalonnage global . 106 3 Applications : détermination de distance de λ Tau . 108 4 Conclusion . 110 V Impact de la rotation sur la relation brillance de surface-couleur 113 1 Effet de la rotation sur la structure d’une étoile . 114 1.1 Le modèle de roche pour le rotateur rapide . 114 1.2 L’effet Von Zeipel . 116 2 Simulations d’observations avec VEGA/CHARA . 118 2.1 Modèles théoriques de rotateurs . 118 2.2 Principe d’estimation de la visibilité . 119 2.3 Le modèle M3 comme exemple . 122 3 Quantification de l’effet de la rotation sur la relation BSC . 123 4 Rotateur rapide δ Per................................. 126 5 Conclusion . 128 Conclusion et perspectives 129 ANNEXES 132 A Improving the surface brightness-color relation for early-type stars using op- tical interferometry 133 B Performance, results, and prospects of the visible spectrograph VEGA on CHARA 147 3 Table des matières C The impact of the rotation on the surface brightness of early-type stars 159 D Measurements of eight early-type stars angular diameters using VEGA/CHARA interferometer 163 E The Araucaria Project : the Baade-Wesselink projection factor of pulsating stars and interferometric contribution to the eclipsing binaries technique of distance determination 169 F Calibration of the surface-brightness relation of B early type stars : Toward a very accurate distance determination of LMC eclipsing binaries 175 Références bibliographiques 181 4 Liste des figures I.1 L’univers dans son ensemble . 17 I.2 Les échelles de distance dans l’univers . 19 I.3 Relation de Hubble . 24 I.4 Relation brillance de surface de Wesselink . 28 I.5 Algorithme de mes travaux de recherche . 31 II.1 L’interféromètre de Michelson . 35 II.2 Le grand interféromètre à deux télescopes (GI2T) . 36 II.3 Schéma représentant l’interféromètre du VLTI . 38 II.4 Propagation des ondes dans l’atmosphère . 40 II.5 Importance de l’optique adaptative . 42 II.6 Système de l’optique adaptative . 43 II.7 La base projetée sur le ciel . 45 II.8 Schéma de l’expérience des trous d’Young . 46 II.9 Résolution progressive d’une étoile . 50 II.10 Carte de brillance d’une étoile . 51 II.11 Module de la TF (|γ12|) .............................. 52 II.12 Ligne de base de l’interféromètre . 53 II.13 Visibilité des franges en fonction de la fréquence spatiale . 53 II.14 Schéma du réseau interférométrique CHARA . 55 II.15 Configuration des bases de CHARA . 56 II.16 Représentation schématique du plan optique de CHARA . 57 II.17 Very Large Telescope Interferometer . 59 II.18 Sydney University Stellar Interferometer . 60 II.19 Navy Prototype Optical Interferometer . 61 II.20 Infrared Spatial Interferometer . 62 5 Liste des figures III.1 Table optique qui relie VEGA à CHARA . 67 III.2 Ajustement de visibilités calibrées mesurées avec VEGA . 71 III.3 Interfaces de l’outil Aspro2 . 75 III.4 Création de proposal de mon programme V38 . 77 III.5 Création de la "Starlist" . 78 III.6 Choix de la stratégie d’observation . 79 III.7 Recherche des calibrateurs avec SearchCal . 80 III.8 La densité spectrale dans le cas d’un interféromètre à deux télescopes . 84 III.9 Séquence d’observation des visibilités brutes . 86 III.10 La visibilité calibrée en fonction de la fréquence spatiale . 90 III.11 Ajustement des données VEGA pour δ Cyg et ζ Peg . 92 IV.1 Diagramme explicatif de différentes étapes de la correction photométrique. 101 IV.2 Relation entre la brillance de surface Sv et l’indice de couleur (V-K)0 ..... 105 IV.2 Suite. 106 IV.3 Relation S vs (V K) ............................. 107 V − 0 IV.4 Zoom de la Figure IV.3 .............................. 108 V.1 Systèmes de coordonnées pour un rotateur rapide . 115 V.2 Modèle de Roche de trois étoiles identiques . 117 V.3 Configuration de CHARA utilisée dans cette étude . 119 V.4 Plan (u,v) associé aux configurations du Tableau V.2 .............. 120 V.5 Modèles pour différentes inclinaisons (i)..................... 121 V.6 Modèles pour différentes vitesses rotationnelles (V c).............. 121 V.7 La brillance de surface vs.
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