The Sun

A wealth of new experimental and theoretical results has been obtained in solar physics since the first edition of this textbook appeared in 1989. Thus all nine chapters have been thoroughly revised, and about 100 pages and many new illustrations have been added to the text. The additions include element diffusion in the solar interior, the recent neutrino experiments, methods of image restoration, observational devices used for spectroscopy and polarimetry, and new developments in helioseismology and numerical simulation. The book takes particular advantage of the results of several recent space missions, which lead to substantial progress in our understanding of the Sun, from the deep interior to the corona and solar wind.

Contenu

1. Characteristics of the Sun.- 1.1 Distance.- 1.2 Mass.- 1.3 Radius.- 1.4 Luminosity.- 1.5 Spectral Energy Distribution.- 1.5.1 Energy Flux and Intensity.- 1.5.2 The Visible.- 1.5.3 The Infrared.- 1.5.4 The Radio Spectrum.- 1.5.5 The Ultraviolet.- 1.5.6 Extreme Ultraviolet and X-rays.- 1.5.7 Color Indices.- 1.6 Bibliographical Notes.- 2. Internal Structure.- 2.1 Construction of a Model.- 2.1.1 The Evolutionary Sequence.- 2.1.2 The Standard Model.- 2.2 Age and Pre-Main-Sequence Evolution.- 2.3 Model Ingredients.- 2.3.1 Conservation Laws.- 2.3.2 Energy Transport.- 2.3.3 Element Diffusion in the Interior.- 2.3.4 The Equation of State.- 2.3.5 The Entropy.- 2.3.6 Nuclear Energy Sources.- 2.3.7 The Opacity.- 2.3.8 Boundary Conditions and Method of Solution.- 2.4 Results for a Standard Solar Model.- 2.4.1 General Evolution.- 2.4.2 Neutrinos.- 2.5 Non-Standard Models.- 2.5.1 The Low-Z Model.- 2.5.2 Rapidly Rotating Core.- 2.5.3 Internal Magnetic Field.- 2.5.4 The Internally Mixed Model.- 2.6 Bibliographical Notes.- 3. Tools for Solar Observation.- 3.1 Limitations.- 3.1.1 General Difficulties.- 3.1.2 Seeing: Description and Definitions.- 3.1.3 Seeing: How to Live with It.- 3.1.4 Adaptive Optics.- 3.1.5 Image Restoration.- 3.2 High-Resolution Telescopes.- 3.2.1 Image Scale.- 3.2.2 Mirrors for Fixed Telescopes.- 3.2.3 Telescopes with Long Primary Focus.- 3.2.4 Telescopes with Short Primary Focus.- 3.3 Spectrographs and Spectrometers.- 3.3.1 The Grating Spectrograph.- 3.3.2 The Fourier Transform Spectrometer.- 3.3.3 The Measurement of Line Shifts.- 3.4 Filters and Monochromators.- 3.4.1 The Lyot Filter.- 3.4.2 Tuning: the Universal Filter.- 3.4.3 A Tunable Michelson Interferometer.- 3.4.4 The Fabry-Perot Interferometer.- 3.4.5 A Magneto-Optical Filter.- 3.4.6 A Double Monochromator.- 3.4.7 The Spectroheliograph.- 3.5 Polarimetry.- 3.5.1 Zeeman Splitting.- 3.5.2 Polarized Light.- 3.5.3 Unno's Equations.- 3.5.4 Solar Polarimeters.- 3.5.5 Scattering Polarization and Hanle Effect.- 3.6 Special-Purpose Instruments.- 3.6.1 The Pyrheliometer.- 3.6.2 Neutrino Detectors.- 3.6.3 The Coronagraph.- 3.7 Bibliographical Notes.- 4. The Atmosphere.- 4.1 Radiative Transfer - Local Thermodynamic Equilibrium.- 4.1.1 The Equation of Transfer.- 4.1.2 Various Equilibria.- 4.1.3 Absorption Lines in LTE.- 4.2 Radiative Transfer - Statistical Equilibrium.- 4.2.1 Model Assumptions.- 4.2.2 Line Radiation and Einstein Coefficients.- 4.2.3 Continuum Radiation.- 4.2.4 Collisions.- 4.2.5 The Source Function.- 4.2.6 The Equations of Statistical Equilibrium.- 4.3 Atmospheric Models.- 4.3.1 Limb Darkening.- 4.3.2 Model Calculations in LTE.- 4.3.3 Models with Departures from LTE.- 4.4 The Chemical Composition of the Sun.- 4.4.1 Spectrum Synthesis.- 4.4.2 The Light Elements Lithium, Beryllium, and Boron.- 4.4.3 Helium.- 4.5 Bibliographical Notes.- 5. Oscillations.- 5.1 Observations.- 5.1.1 Five-Minute Oscillations.- 5.1.2 The Spectrum of Solar Oscillations.- 5.1.3 Low-Degree p Modes.- 5.1.4 Line Width and Line Asymmetry.- 5.2 Linear Adiabatic Oscillations of a Non-Rotating Sun.- 5.2.1 Basic Equations.- 5.2.2 Spherical Harmonic Representation.- 5.2.3 The Cowling Approximation.- 5.2.4 Local Treatment.- 5.2.5 Boundary Conditions.- 5.2.6 Asymptotic Results.- 5.3 Helioseismology.- 5.3.1 Direct Modeling and Inversion.- 5.3.2 Speed of Sound in the Solar Interior.- 5.3.3 Depth of the Convection Zone.- 5.3.4 Chemical Constitution.- 5.3.5 Equation of State.- 5.3.6 Internal Mixing.- 5.3.7 Precise Determination of the Solar Radius.- 5.3.8 Internal Rotation.- 5.3.9 Travel Time and Acoustic Imaging.- 5.4 Excitation and Damping.- 5.4.1 The ? Mechanism.- 5.4.2 Stochastic Excitation by Convection.- 5.5 Bibliographical Notes.- 6. Convection.- 6.1 Stability.- 6.2 Mixing-Length Theory.- 6.2.1 The Local Formalism.- 6.2.2 Numerical Test Calculations.- 6.2.3 Overshooting: A Non-local Formalism.- 6.3 Granulation.- 6.3.1 The Observed Pattern.- 6.3.2 Models.- 6.3.3 Mean Line Profiles.- 6.4 Mesogranulation.- 6.5 Supergranulation.- 6.5.1 The Velocity Field and the Network.- 6.5.2 Convective Nature.- 6.5.3 The Effect of Rotation.- 6.6 Giant Cells.- 6.6.1 Tracer Results.- 6.6.2 Spectroscopic Results.- 6.7 Bibliographical Notes.- 7. Rotation.- 7.1 Axis of Rotation.- 7.2 Oblateness.- 7.2.1 Origin.- 7.2.2 Measurements.- 7.3 Rotational History.- 7.3.1 The Initial State.- 7.3.2 Torques.- 7.3.3 Evolution of the Solar Rotation.- 7.4 The Angular Velocity of the Sun.- 7.4.1 The Internal Angular Velocity.- 7.4.2 The Angular Velocity at the Surface.- 7.4.3 Meridional Circulation.- 7.4.4 Correlation of Flow Components.- 7.5 Models of a Rotating Convection Zone.- 7.5.1 Conservation of Angular Momentum.- 7.5.2 Mean-Field Models.- 7.5.3 Explicit Models.- 7.6 Bibliographical Notes.- 8. Magnetism.- 8.1 Fields and Conducting Matter.- 8.1.1 The Induction Equation.- 8.1.2 Electrical Conductivity on the Sun.- 8.1.3 Frozen Magnetic Field.- 8.1.4 The Magnetic Force.- 8.2 Flux Tubes.- 8.2.1 Concentration of Magnetic Flux.- 8.2.2 Observational Evidence for Flux Tubes.- 8.2.3 Vertical Thin Flux Tubes.- 8.2.4 Curved Thin Flux Tubes.- 8.2.5 Thermal Structure of Photospheric Tubes.- 8.3 Sunspots.- 8.3.1 Evolution and Classification.- 8.3.2 Sunspot Models.- 8.3.3 Sunspots and the "Solar Constant".- 8.3.4 Dots and Grains.- 8.3.5 Oscillations in Sunspots.- 8.3.6 The Evershed Effect.- 8.4 The Solar Cycle.- 8.4.1 Global Magnetism.- 8.4.2 Mean-Field Electrodynamics.- 8.4.3 The Kinematic ?? Dynamo.- 8.4.4 The Magnetohydrodynamic Solar Dynamo.- 8.5 Bibliographical Notes.- 9. Chromosphere, Corona, and Solar Wind.- 9.1 Empirical Facts.- 9.1.1 The Chromosphere.- 9.1.2 The Transition Region.- 9.1.3 The Corona.- 9.1.4 The Wind.- 9.2 Consequences of High Temperature.- 9.2.1 Heat Conduction.- 9.2.2 Expansion.- 9.3 The Magnetic Field in the Outer Atmosphere.- 9.3.1 Magnetic Field Measurements.- 9.3.2 Potential Field Extrapolation.- 9.3.3 The Force-Free Field.- 9.3.4 Prominences.- 9.3.5 Magnetic Braking of Solar Rotation.- 9.4 The Energy Balance.- 9.4.1 Needs.- 9.4.2 Heating.- 9.5 Explosive Events.- 9.5.1 Flares and Other Eruptions.- 9.5.2 Release of Magnetic Energy.- 9.6 Bibliographical Notes.- List of Symbols.- References.