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Extrasolar Planets Edited by Rudolf Dvorak Related Titles S.N. Shore Astrophysical Hydrodynamics An Introduction 2007 ISBN 978-3-527-40669-2 M. Salaris Evolution of Stars and Stellar Populations 2005 E-Book ISBN: 978-0-470-09222-4 S.N. Shore The Tapestry of Modern Astrophysics 2003 ISBN 978-0-471-16816-4 Extrasolar Planets Formation, Detection and Dynamics Edited by Rudolf Dvorak WILEY-VCH Verlag GmbH & Co. KGaA The Editor All books published by Wiley-VCH are carefully produced. Nevertheless, authors, editors, and publisher do not warrant the information contained in these Prof. Dr. Rudolf Dvorak books, including this book, to be free of errors. Readers University of Vienna are advised to keep in mind that statements, data, illustrations, procedural details or other items may Institute for Astronomy inadvertently be inaccurate. Tuerkenschanzstrasse 17 1180 Wien Library of Congress Card No.: applied for Austria British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library. Bibliographic information published by the Deutsche Nationalbibliothek Die Deutsche Nationalbibliothek lists this publication in the Deutsche Nationalbibliografie; detailed bibliographic data are available on the Internet at http://dnb.d-nb.de ¤ 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim All rights reserved (including those of translation into other languages). No part of this book may be reproduced in any form – by photoprinting, microfilm, or any other means – nor transmitted or translated into a machine language without written permission from the publishers. Registered names, trademarks, etc. used in this book, even when not specifically marked as such, are not to be considered unprotected by law. Printed in the Federal Republic of Germany Printed on acid-free paper Typesetting Uwe Krieg, Berlin Printing betz-druck GmbH, Darmstadt Bookbinding Litges & Dopf GmbH, Heppenheim ISBN: 978-3-527-40671-5 V Contents Preface XIII List of Contributors XVII 1 Planetary Masses and Orbital Parameters from Radial Velocity Measurements 1 C. Beaugé, S. Ferraz-Mello, and T. A. Michtchenko 1.1 Exoplanet Detection 1 1.2 Radial Velocity in Astrocentric Elements 2 1.3 Orbital Fits from Radial Velocity Curves 8 1.3.1 Primary Parameters 8 1.3.2 Secondary Parameters 11 1.3.3 N-Body Fits 13 1.4 Coordinate Systems and Equations of Motion 16 1.4.1 Barycentric Hamiltonian Equations 17 1.4.2 Jacobi Hamiltonian Formalism 17 1.4.3 Poincaré Hamiltonian Formalism 19 1.4.4 Generalized Orbital Elements and Delaunay Variables 20 1.4.5 Comparisons Between Coordinate Systems 22 1.4.6 The Conservation of the Angular Momentum 24 2 Terrestrial Planets in Extrasolar Planetary Systems 27 R. Dvorak and E. Pilat-Lohinger 2.1 Introduction 28 2.2 The Methods of Investigation 30 2.3 Basics of the Formation of Terrestrial Planets 33 2.4 Stability Studies of Terrestrial Planets 34 2.4.1 The G2 Systems and Gliese 777A 34 2.4.2 Theoretical and Numerical Stability Investigation of the G4 and EPS HD108874 37 Extrasolar Planets: Formation, Detection and Dynamics. Edited by Rudolf Dvorak Copyright © 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim ISBN: 978-3-527-40671-5 VI Contents 2.5 A Global Approach: The Exocatalogue 44 2.6 Terrestrial Planets in Multiplanetary Systems 45 2.6.1 The Changing Story of HD74156 46 2.7 Conclusions 47 3 Mission Requirements: How to Search for Extrasolar Planets 51 M. Fridlund and L. Kaltenegger 3.1 Introduction 51 3.2 Formulation of the Problem and High-level Scientific Requirements 54 3.3 Comparative Planetology 56 3.4 Methods and the Need to go into Space 57 3.5 Space Missions 61 3.5.1 MOST – The First Step 61 3.5.2 CoRoT – The First True Exoplanetary Mission 62 3.5.3 Kepler – The Exploration Continues 63 3.5.4 The Role of the Herschel Mission in the Search for Other Earths 63 3.5.5 GAIA – The First Global Survey Instrument and the Cosmic Census 64 3.5.6 SIM – Planet Quest 65 3.6 Darwin and the Terrestrial Planet Finder(s) – Other Worlds with Life as we Know it 65 3.6.1 Nulling Interferometry 67 3.6.2 Background and Foreground Flux 72 3.6.3 Model of an Exosolar System 74 3.7 The Future – Mission Accomplished? 75 4 Biomarkers Set in Context 79 L. Kaltenegger and F. Selsis 4.1 Introduction 79 4.2 Biomarkers 81 4.3 Biomarker Signatures in Different Wavelength Ranges 83 4.4 Potential Biomarkers 84 4.5 A Habitable Planet 86 4.6 Oxygen and Ozone Production on Earth 87 4.7 Cloud Features 89 4.8 Biomarkers and their Evolution over Geological Times on Earth 89 4.9 Planets around Different Stars 91 4.10 Abiotic Sources 93 4.11 Biomarkers Detection Set in Context 94 4.11.1 Temperature and Radius of the Planets 94 4.12 Orbital Flux Variations 95 4.13 Summary 97 Contents VII 5 The Formation of Resonant Planetary Systems 99 W. Kley and Z. Sándor 5.1 The Solar System 99 5.2 Extrasolar Systems in Mean-motion Resonance 101 5.3 Planet–Disk Interaction 103 5.4 Resonant Capture 105 5.4.1 Hydrodynamical Studies 105 5.4.2 Forced Migration 108 5.4.3 Second Fundamental Model of Resonance 109 5.4.4 Outcome of Resonant Encounters 112 5.5 Specific Systems 113 5.5.1 GJ 876: A Case of Adiabatic Migration 114 5.5.2 Formation of Systems HD 128311 and HD 73526 through Mixed Scenarios 116 5.6 Summary 122 6 Impact of Stellar Activity on the Evolution of Planetary Atmospheres and Habitability 127 H. Lammer, M. L. Khodachenko, H. I. M. Lichtenegger, and Y. N. Kulikov 6.1 Introduction 127 6.2 The Habitable Zone Around Main-sequence Stars 130 6.2.1 General Definition of the Habitable Zone 130 6.2.2 The Circumstellar Habitable Zone 132 6.2.3 Geophysical Factors which Influence Habitability 133 6.2.4 Stellar Radiation and Particle Forcing 135 6.3 The Impact of the Stellar Radiation on the Upper Atmosphere 137 6.3.1 Heating, Cooling, and Expansion of the Upper Atmosphere 138 6.3.2 Thermal Escape of Atmosphere and Water 139 6.4 Stellar Wind and CME Plasma Interaction with Planetary Atmospheres 140 6.4.1 Collision Probability Between Planets and CMEs 142 6.4.2 Atmospheric Mass-loss Caused by CME Exposure 144 6.5 Discussion 146 7 Dynamics of the Extrasolar Planetary Systems 151 T. A. Michtchenko, S. Ferraz-Mello, and C. Beaugé 7.1 Introduction 151 7.2 Classification of the Systems with Respect to their Dynamical Behavior 153 7.3 Numerical Integrations, Dynamical Maps and Modeling 155 7.4 Secular Dynamics: υ Andromedae Planets c and d 156 VIII Contents 7.4.1 Planar Dynamics 158 7.4.2 Dynamical Maps 161 7.4.3 3D Dynamics 163 7.4.4 Inclination and Planetary Mass Indetermination 165 7.4.5 Proximity to Mean-motion Resonances 166 7.5 Resonant Dynamics: Planetary Systems in Mean-Motion Resonances 167 7.5.1 GJ 876 Planets c and b 168 7.5.2 HD 82943 Planets c and b 171 7.6 Nearly Resonant Systems with Small Eccentricities 174 8 Planets in Double Stars 179 E. Pilat-Lohinger and R. Dvorak 8.1 Introduction 179 8.2 Computations and Methods 181 8.3 General Stability Studies of Planetary Motion in Double-star Systems 182 8.3.1 S-type Motion 182 8.3.2 P-type Motion 188 8.3.3 L-type Motion 193 8.4 Application to Real Systems 194 8.5 Influence of the Secondary 197 8.6 Detected Planets in Binary Systems 200 8.7 Summary 201 9 The Transit Method 207 H. Rauer and A. Erikson 9.1 Introduction 207 9.2 Overview of Detected Transiting Planets 209 9.2.1 From Predictions to Regular Detections 209 9.2.2 Basic Parameters of the Known Transiting Planets 213 9.3 The Transit Signal 216 9.4 From Light Curves to Planets 220 9.4.1 Transit Signal Detection 220 9.4.2 Confirmation or Rejection 221 9.5 Characterizing Factors of Transit Searches 224 9.5.1 The Effective Duty Cycle 224 9.5.2 Target Field Selection 226 9.5.3 Noise Sources Affecting the Photometry 226 9.6 Detection Probabilities 229 9.7 Further Characterization of Transiting Planets 231 9.8 Future Prospects 233 Contents IX 10 US Programs and Space Missions for Extrasolar Planet Research 241 P. K. Seidelmann 10.1 Introduction 241 10.2 Kepler 243 10.3 SIM PlanetQuest 244 10.4 Terrestrial Planet Finder – Coronograph (TPF-C) 245 10.5 Terrestrial Planet Finder – Infrared (TPF-I) 246 10.6 Spitzer Space Telescope 246 10.7 James Webb Space Telescope (JWST) 247 10.8 Microvariability and Oscillations of Stars (MOST) 248 10.9 Stratospheric Observatory for Infrared Astronomy (SOFIA) 249 10.10 Keck Interferometer 249 10.11 Large Binocular Telescope Interferometer (LBTI) 250 10.12 Palomar Observatory 251 10.13 Pan-STARRS 252 10.14 Thirty Meter Class Telescopes 252 10.15 Scientific Results 253 10.16 Conclusions 255 11 Habitable Zones in Extrasolar Planetary Systems 257 W. von Bloh, C. Bounama, and S. Franck 11.1 Introduction 257 11.2 Modeling the Earth System 259 11.2.1 Planetary Climate 260 11.2.2 The Global Carbon Cycle 260 11.2.3 Silicate-Rock Weathering Rate 261 11.2.4 Biological Productivity 262 11.2.5 Geodynamics 263 11.3 The Habitable Zone in the Solar System 266 11.4 Habitable Zone Around Main-sequence Stars 269 11.5 Dynamic Habitability in Extrasolar Planetary Systems 272 11.5.1 Orbital Stability 273 11.5.2 Results for 86 Extrasolar Planetary Systems 275 11.6 Summary 278 Index 285 XI Prolog The plans for this book on extrasolar planets go back to 2005, when the pub- lisher WILEY-VCH approached me to edit a book on this hot topic in astron- omy.
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