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A Multi-Wavelength Study of Protoplanetary Disks with Astronomical Unit Resolution Narges Jamialahmadi

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A Multi-Wavelength Study of Protoplanetary Disks with Astronomical Unit Resolution Narges Jamialahmadi A multi-wavelength study of protoplanetary disks with astronomical unit resolution Narges Jamialahmadi To cite this version: Narges Jamialahmadi. A multi-wavelength study of protoplanetary disks with astronomical unit resolution. Other. Université Nice Sophia Antipolis, 2015. English. NNT : 2015NICE4129. tel- 01314146 HAL Id: tel-01314146 https://tel.archives-ouvertes.fr/tel-01314146 Submitted on 6 Jul 2017 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. UNIVERSITE´ NICE SOPHIA ANTIPOLIS Eole Doctorale de Sciences Fondamentales et Appliqu´ees European Southern Observatory (ESO) THESE pour obtenir le titre de Docteur en Sciences de l’UNIVERSITE Nice Sophia Antipolis de l’ESO Discipline : SCIENCES DE L’UNIVERS pr´esent´ee et soutenue par Narges JAMIALAHMADI Une ´etude multi longueur d’onde des disques protoplan´etaires `al’´echelle de l’unit´eastronomique A multi-wavelength study of protoplanetary disks with astronomical unit resolution Th`ese dirig´ee par: Bruno Lopez, Philippe Berio Th`ese dirig´ee a l’ESO par: Jean-Philippe Berger Soutenue le 16 D´ecembre Jury: Pr´esident : Alessandro Morbidelli Directeur de Recherche, Lagrange, OCA Rapporteurs : Jean-Francois Gonzalez Maˆıtre de Conf´erence, Observatoire de Lyon Stefan Kraus Professeur Associ´e, University of Exeter Examinateur: Jean-PhilippeBerger DirecteurdeRecherche,ESO Directeur de th`ese : Bruno Lopez Directeur de Recherche, Lagrange, OCA Co-Directeur de th`ese : Philippe Berio Ing´enieur de Recherche, Lagrange, OCA Abstract Planetary systems are born in circumstellar gas and dust disks surrounding Young Stellar Objects (YSOs). To understand how planetary systems form, a detailed knowledge of the structure and evolution of these disks is required. Although, this is almost well understood for the regions of the disks observed with a spatial resolution of several AUs, the structure of these disks probed at a few AU scale and especially inward of 1 AU remains a puzzle. In recent years, it has become possible to directly spatially resolve the inner region of protoplanetary disks with optical interferometry technique. The context of this thesis is a multi-wavelength investigation of the protoplanetary disks evolution by determining their density distribution, their temperature distribution, the size and composition of the dust components and finally the kinematics of the gas. I have developed my thesis following three complementary wavelength domains: study of the photosphere of the star and its nearby gaseous disk through visible interferometry, study of the radial and vertical structure of the inner rim of a pre-transitional disk at fractions of an AU through near-IR interferometry, and, the characterization of the disk regions at a few AUs from the central star through spectroscopic and mid-IR interferometry. To analyse the visible-, near- and mid-IR interferometric observations, I have focused my attention on three well known sources, 51 OPh, HD 100546 and MWC 480 respec- tively that they have not been observed in these wavelengths. Visible interferometric observations can probe the photosphere of a resolved source in the continuum as well as the geometry and the kinematics of the gaseous disk producing the Hα line or Ca II triplet line on sub-AU scale. These observations allow to derive the stellar parameters, e.g, diameter, mass, temperature and to constrain the extension of the emission line and to understand the physical process of the gas such as accretion/outflow mechanism nearby the central star. Near-IR interferometric observations probe the hot gas and dust distribution at a fraction of an AU from the central star and allow to understand the kinematics of the gas as well as hot dust properties and its physical mechanism for the disk evolution and planet formation. Mid-IR interferometric observations mostly probe warm dust from the most inner region up to a few AU and allow to investigate the dust properties and in their emission regime. iii Acknowledgements This thesis would not have done without helps of people around me during my stay in Nice and Munich. In the first day of my arrival to Nice in 2th December 2011, the first person I met in the airport was Bruno Lopez, one of my advisors. Based on the way of his behaviour (kindness) in the first day, I considered him like a father who is so supportive. I felt that I am so convenient to talk to him about work or any other topics. Then, I came to know with Philippe Berio my another supervisor. I think every one has at least one sample in her/his life. During my PhD, Philippe for me was a sample of kindness and patience, an understanding person who never considered my weakness but my strengths. My questions never stopped him answering me and he was a person who motivated me to keep doing my research. This research has largely benefited from the advices of my colleague Olivier Chesneau, who passed away last spring. I wish to acknowledge his help. Thanks Philipe Berio, step by step, I started working with VEGA group in Nice and I found them so friendly. I learnt lots of things about observations since I never had any experiences on observations before coming to Nice. Beside my supervisors, working with A. Meilland, N. Nardetto, Ph. Stee and others in VEGA group motivated me to work on YSOs and stellar physics more than before. I am mostly grateful to Anthony Meilland for all his helps in VEGA observations and teaching me to use his code during my thesis. Thanks to planetology group, A. Morbidelli, A. Crida, P. Tanga, Alexis Matter and others in this group for useful discussions. I appreciate all helps of Sebastien Flament during my thesis helping me in writing numerical codes. I express my gratitude to Thorsten Ratzka in the last year of my PhD. I am always grateful of M. Vennier, F. Millour, S. Lagarde, T. Lanz, F. Vakili and E. Fossat for many useful discussions during these years. During these three years in Nice, I got many friends with whom I could share my happiness and some times problems of my life and work. I am really grateful of my friends ( their names in order of coming to know them): Sibilla, Masinissa, Wassilla, Suvendu, Arwa, Aurelie, Korhan, Laurent, Kaveh, Judit, Mamadu, Sinan, Zeinab, Samir, Husne, Onelda, Alkis, Gaetan, Alvaro, Sarunas, Reda, Srivatsan and many others friends. It was a pleasure to be officemate with Suvendu, Roxanne, Carolyne and Laurence. Our warm and friendly chatting (even in French) was inducing lots of positive energies to me. I do thank Nathalie, Michel and Khaled, Karima, Nadia and others in canteen whom their smiles and their great foods were boosting my energy to keep woking. v In the last year of my PhD, I got accepted for ESO studentship and started working with Jean-Philippe Berger. Thanks to him I learnt a lot of things concerning radiative transfer code and PIONIER/VLTI. The beginning days of arriving to cold Munich was hard to me to be far from all my belongs in Nice, but I found him friendly that I felt comfortable to chat with him about works and other topics. I am really grateful of Andrea Chiavassa who did lots of helps either code problems or other useful discussions for my future career during the first month of my staying at ESO. Thanks Marco Di Pascal who helped me the first days of arrival to Garching to introduce me to PhD and fellows at ESO. I really appreciate all useful chats with my Iranian friends, Maryam, Mahsa, Ghazale, Masuod and Mohammad at MPE. During these years, I never forget supports of my loves, i.e., my parents, sisters and brothers. The most my greatest acknowledge to Juries to take time and review my thesis and attend to my defence. A the end, I strongly appreciate my efforts to overcome most of problems I faced during these years at OCA and at ESO. ’The first rule is to have vision for your life, ’the second is to believe in your ability to figure things out, ’the third is to be patient but always persistent, ’the forth is to respect and love other people.’ –Narges Dedicated to My parents, sisters and brothers ix Contents Abstract iii Acknowledgements v List of Figures xiv List of Tables xx Introduction xxvi 1 Scientific overview 1 1.1 Star formation ................................. 1 1.2 Protoplanetary disk phase ........................... 3 1.3 Planet formation ................................ 5 1.4 The radial structure of the disk ........................ 6 1.5 The vertical structure of the disk ....................... 9 1.6 Dust properties ................................. 13 1.6.1 Dust opacity .............................. 14 1.6.2 Dust scattering ............................. 18 1.6.3 Mie Theory ............................... 20 1.7 Protoplanetary disk Models .......................... 21 1.7.1 Transitional and Pre-transitional Disks . 25 1.8 Radiative transfer ............................... 26 1.8.1 The radiative transfer problem .................... 27 1.8.2 Monte Carlo radiative transfer: MCFOST . 28 2 An introduction to optical/IR interferometry 30 2.1 Why Spatial Interferometry? ......................... 30 2.1.1 The Electromagnetic field ....................... 32 2.1.2 The Young’s experiment ........................ 34 2.1.3 The Fizeau Interferometry ....................... 36 2.1.4 Light coherence ............................. 39 2.1.5 Complex degree of mutual coherence . 40 2.1.6 Visibility ................................ 48 2.1.7 Phase .................................. 49 xi Contents xii 2.1.8 The differential phase ........................
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