Asteroseismology, 2010 Astronomy and Astrophysics Library Series

Understanding the stars is the bedrock of modern astrophysics. Stars are the source of life. The chemical enrichment of our Milky Way and of the Universe withallelementsheavierthanlithiumoriginatesintheinteriorsofstars.Stars arethe tracersofthe dynamics ofthe Universe,gravitationallyimplying much more than meets the eye. Stars ionize the interstellar medium and re-ionized the early intergalactic medium. Understanding stellar structure and evolution is fundamental. While stellar structure and evolution are understood in general terms, we lack important physical ingredients, despite extensive research during recent decades.Classicalspectroscopy,photometry,astrometryandinterferometryof stars have traditionally been used as observational constraints to deduce the internal stellar physics. Unfortunately, these types of observations only allow the tuning of the basic common physics laws under stellar conditions with relatively poor precision. The situation is even more worrisome for unknown aspects of the physics and dynamics in stars. These are usually dealt with by using parameterised descriptions of, e.g., the treatments of convection, rotation,angularmomentumtransport,theequationofstate,atomicdi?usion andsettlingofelements,magneto-hydrodynamicalprocesses,andmore.There is a dearth of observational constraints on these processes, thus solar values areoftenassignedtothem.Yetitishardtoimaginethatonesetofparameters is appropriate for the vast range of stars.

1 Introducing Asteroseismology.- 1.1 Introduction.- 1.2 1-D Oscillations.- 1.3 2-D Oscillations in a Drum Head.- 1.4 3-D Oscillations in Stars.- 1.5 An Asteroseismic HR Diagram for p-Mode Pulsators.- 1.6 A Pulsation HR Diagram.- 2 Stellar Oscillations across the Hertzsprung-Russell Diagram.- 2.1 Stellar Evolution in a Nutshell.- 2.2 Variability Studies from Large-Scale Surveys.- 2.3 Oscillations Near the Main Sequence.- 2.4 Oscillations in Pre-Main-Sequence Stars.- 2.5 Pulsations in Evolved Stars with M ≤ 9M.- 2.6 Pulsations in Evolved Stars with M ≥ 9M.- 2.7 Compact Oscillators.- 2.8 Pulsations in Binaries.- 2.9 Conclusions.- 3 Theory of Stellar Oscillations.- 3.1 General Hydrodynamics.- 3.2 Equilibrium Stellar Structure.- 3.3 Equations of Linear Stellar Oscillations.- 3.4 Asymptotic Theory of Stellar Oscillations.- 3.5 Computed Properties of Modes of Oscillation.- 3.6 Variational Properties of Stellar Adiabatic Oscillations.- 3.7 Driving Mechanisms.- 3.8 Effects of Rotation.- 4 Observational Techniques.- 4.1 Duty Cycle.- 4.2 Time.- 4.3 Photometry.- 4.4 Spectroscopy.- 5 Frequency Analysis.- 5.1 Harmonic Analysis by Least Squares.- 5.2 Non-parametric Frequency Analysis Methods.- 5.3 Parametric Frequency Analysis Methods.- 5.4 Significance Criteria.- 5.5 Error Estimation of the Derived Frequencies.- 5.6 The use of Weights in Merging different Data Sets.- 5.7 Damped Oscillations.- 5.8 Eliminating Aliases.- 5.9 Conclusions.- 6 ModeIdentification.- 6.1 Mode Identification from Multicolour Photometry.- 6.2 Mode Identification from High-Resolution Spectroscopy.- 6.3 Mode Identification from Combined Photometry and Spectroscopy.- 6.4 Towards Mode Identification from Combined Interferometry and Spectroscopy?.- 6.5 Towards Mode Identification from Eclipse Mapping?.- 7 Applications of Asteroseismology.- 7.1 Helioseismology.- 7.2 Solar-Like Pulsators.- 7.3 Heat Driven Main Sequence Stars.- 7.4 Compact Pulsators.- 8 The Future.- 8.1 Space Missions.- 8.2 Ground-Based Networks and Antarctica.- A Summary of the Different Classes of Stellar Pulsators.- B Properties of Legendre Functions and Spherical Harmonics.- C Mathematical Preliminaries.- D Adiabatic Oscillations in an Isothermal Atmosphere.- E Asymptotic Theory of Stellar Oscillations.- Bibliography.- Subject Index.- Object Index.- Acronym Definition Index.