Theory of Stellar Atmospheres: An Introduction to Astrophysical Non-equilibrium Quantitative Spectroscopic Analysis

945 Pages·12.581 MB·English

by  Ivan Hubený, Dimitri Mihalas

Theory of Stellar Atmospheres
PRINCETONSERIESINASTROPHYSICS
EditedbyDavidN.Spergel
TheoryofRotatingStars,byJean-LouisTassoul
TheoryofStellarPulsation,byJohnP.Cox
GalacticDynamics,SecondEdition,byJamesBinneyandScottTremaine
DynamicalEvolutionofGlobularClusters,byLymanSpitzer,Jr.
SupernovaeandNucleosynthesis:AnInvestigationoftheHistoryofMatter,
fromtheBigBangtothePresent,byDavidArnett
UnsolvedProblemsinAstrophysics,editedbyJohnN.BahcallandJeremiahP.Ostriker
GalacticAstronomy,byJamesBinneyandMichaelMerrifield
ActiveGalacticNuclei:FromtheCentralBlackHoletotheGalacticEnvironment,
byJulianH.Krolik
PlasmaPhysicsforAstrophysics,byRussellM.Kulsrud
ElectromagneticProcesses,byRobertJ.Gould
ConversationsonElectricandMagneticFieldsintheCosmos,byEugeneN.Parker
High-EnergyAstrophysics,byFulvioMelia
StellarSpectralClassification,byRichardO.GrayandChristopherJ.Corbally
ExoplanetAtmospheres:PhysicalProcesses,bySaraSeager
PhysicsoftheInterstellarandIntergalacticMedium,byBruceT.Draine
TheFirstGalaxiesintheUniverse,byAbrahamLoebandStevenR.Furlanetto
IntroductiontoModelingConvectioninStarsandPlanets:MagneticField,
DensityStratification,Rotation,byGaryGlatzmaier
DynamicsandEvolutionofGalacticNuclei,byDavidMerritt
TheoryofStellarAtmospheres:AnIntroductiontoAstrophysicalNon-equilibrium
QuantitativeSpectroscopicAnalysis,byIvanHubenyandDimitriMihalas
Theory of Stellar Atmospheres
An Introduction to Astrophysical Non-equilibrium
Quantitative Spectroscopic Analysis
Ivan Hubeny and Dimitri Mihalas
PRINCETON UNIVERSITY PRESS
PRINCETON AND OXFORD
Copyright©2015byPrincetonUniversityPress
PublishedbyPrincetonUniversityPress,41WilliamStreet,Princeton,
NewJersey08540
IntheUnitedKingdom:PrincetonUniversityPress,6OxfordStreet,
Woodstock,OxfordshireOX201TW
press.princeton.edu
AllRightsReserved
LibraryofCongressCataloging-in-PublicationData
Hubený,I.(Ivan)
Theoryofstellaratmospheres:anintroductiontoastrophysicalnon-equilibrium
quantitativespectroscopicanalysis/IvanHubenyandDimitriMihalas.
pagescm.—(Princetonseriesinastrophysics)
Includesbibliographicalreferencesandindex.
ISBN978-0-691-16328-4(hardcover:alk.paper)–ISBN978-0-691-16329-1
(pbk.:alk.paper)
1.Stars–Atmospheres.2.Stars–Spectra.I.Mihalas,Dimitri,1939–2013.II.Title.III.Title:
Stellaratmospheres.
QB809.H832015
523.8’6—dc23
2014006308
BritishLibraryCataloging-in-PublicationDataisavailable
ThisbookhasbeencomposedinLATEX
Printedonacid-freepaper.
∞
PrintedintheUnitedStatesofAmerica
10987654321
Dedication
Tomyfriendsandcolleagues,LawrenceAuerandDavidHummer,
andtothememoriesofmyfriendsandteachers
WilliamWilsonMorgan,andWalterStibbs.
D.M.
Tothememoryofmy“scientificmother”andfriendFrançoisePraderie,
andtothememoryofmy“scientificfather,”friend,
andco-authorofthisbook,DimitriMihalas,whosadlypassedaway
justdaysafterthemanuscriptwassubmittedtothepublisher.
I.H.

Contents
Preface xi
Chapter1. WhyStudyStellarAtmospheres? 1
1.1 AHistoricalPrécis 1
1.2 TheBottomLine 15
Chapter2. ObservationalFoundations 20
2.1 WhatIsaStellarAtmosphere? 20
2.2 Spectroscopy 23
2.3 Spectrophotometry 29
2.4 Photometry 32
2.5 Mass,Luminosity,andRadius 46
2.6 InterpretationofColor-MagnitudeDiagrams 53
Chapter3. Radiation 61
3.1 SpecificIntensity 61
3.2 MeanIntensityandEnergyDensity 65
3.3 RadiationFlux 72
3.4 RadiationPressureTensor 75
3.5 ⋆TransformationPropertiesofI,E,F,P 78
3.6 QuantumTheoryofRadiationinVacuum 80
Chapter4. StatisticalMechanicsofMatterandRadiation 86
4.1 ThermodynamicEquilibrium 86
4.2 BoltzmannStatistics 88
4.3 ThermalRadiation 98
4.4 QuantumStatistics 103
4.5 LocalThermodynamicEquilibrium 111
Chapter5. AbsorptionandEmissionofRadiation 113
5.1 AbsorptionandThermalEmission 114
5.2 DetailedBalance 116
5.3 Bound-BoundAbsorptionProbability 121
5.4 Bound-BoundEmissionProbability 130
5.5 Photoionization 136
5.6 Free-FreeTransitions 137
Chapter6. ContinuumScattering 144
6.1 ThomsonScattering:ClassicalAnalysis 145
6.2 ThomsonScattering:QuantumMechanicalAnalysis 150
viii CONTENTS
6.3 ⋆RayleighandRamanScattering 153
6.4 ComptonScattering 159
6.5 ComptonScatteringintheEarlyUniverse 165
Chapter7. AtomicandMolecularAbsorptionCrossSections 170
7.1 HydrogenandHydrogenicIons 171
7.2 Multi-ElectronAtoms 192
7.3 Molecules 208
Chapter8. SpectralLineBroadening 228
8.1 NaturalDampingProfile 228
8.2 DopplerBroadening:VoigtFunction 231
8.3 SemiclassicalImpactTheory 233
8.4 StatisticalTheory:Quasi-StaticApproximation 241
8.5 ⋆QuantumTheoryofLineBroadening 248
8.6 Applications 258
Chapter9. KineticEquilibriumEquations 262
9.1 LTEversusNon-LTE 262
9.2 GeneralFormulation 264
9.3 TransitionRates 267
9.4 LevelDissolutionandOccupationProbabilities 278
9.5 CompleteRateEquations 282
Chapter10. ScatteringofRadiationinSpectralLines 290
10.1 Semiclassical(Weisskopf-Woolley)Picture 291
10.2 ⋆QuantumMechanicalDerivationofRedistributionFunctions 301
10.3 BasicRedistributionFunctions 308
10.4 MoreComplexRedistributionFunctions 321
10.5 EmissionCoefficient 327
Chapter11. RadiativeTransferEquation 334
11.1 Absorption,Emission,andScatteringCoefficients 334
11.2 Formulation 339
11.3 MomentsoftheTransferEquation 347
11.4 Time-Independent,Static,PlanarAtmospheres 352
11.5 Schwarzschild-MilneEquations 361
11.6 Second-OrderFormoftheTransferEquation 367
11.7 Discretization 370
11.8 ProbabilisticInterpretation 373
11.9 DiffusionLimit 374
Chapter12. DirectSolutionoftheTransferEquation 378
12.1 TheProblemofScattering 379
12.2 Feautrier’sMethod 387
12.3 Rybicki’sMethod 397
12.4 FormalSolution 400
12.5 VariableEddingtonFactors 418
CONTENTS ix
Chapter13. IterativeSolutionoftheTransferEquation 421
13.1 AcceleratedLambdaIteration:AHeuristicView 421
13.2 IterationMethodsandConvergenceProperties 425
13.3 AcceleratedLambdaIteration(ALI) 434
13.4 AccelerationofConvergence 440
13.5 AstrophysicalImplementation 443
Chapter14. NLTETwo-LevelandMulti-LevelAtoms 448
14.1 Formulation 448
14.2 Two-LevelAtom 457
14.3 ApproximateSolutions 471
14.4 Equivalent-Two-Level-AtomApproach 482
14.5 NumericalSolutionoftheMulti-levelAtomProblem 488
14.6 PhysicalInterpretation 505
Chapter15. RadiativeTransferwithPartialRedistribution 511
15.1 Formulation 511
15.2 SimpleHeuristicModel 515
15.3 ApproximateSolutions 519
15.4 ExactSolutions 524
15.5 Multi-levelAtoms 533
15.6 Applications 539
Chapter16. StructuralEquations 546
16.1 EquationsofHydrodynamics 546
16.2 1DFlow 554
16.3 1DSteadyFlow 555
16.4 StaticAtmospheres 557
16.5 Convection 558
16.6 StellarInteriors 565
Chapter17. LTEModelAtmospheres 569
17.1 GrayAtmosphere 569
17.2 EquationofState 588
17.3 Non-GrayLTERadiative-EquilibriumModels 593
17.4 ModelswithConvection 604
17.5 LTESpectralLineFormation 606
17.6 LineBlanketing 620
17.7 ModelswithExternalIrradiation 627
17.8 AvailableModelingCodesandGrids 631
Chapter18. Non-LTEModelAtmospheres 633
18.1 OverviewofBasicEquations 633
18.2 CompleteLinearization 645
18.3 OverviewofPossibleIterativeMethods 660
18.4 ApplicationofALI andRelatedMethods 667
18.5 NLTEMetalLineBlanketing 676
18.6 Applications:ModelingCodesandGrids 684