Protostars and Planets VBo ReipurthDavid JewittKlaus Keil

Editors

With 249 collaborating authors

THE UNIVERSITY OF ARIZONA PRESSTucson

in collaboration with

LUNAR AND PLANETARY INSTITUTEHouston

Contents

Scientific Advisory Committee and List of Collaborating Authors xxi

Preface xxiii

PART I: MOLECULAR CLOUDS

Near-Infrared Extinction and Molecular Cloud Structure 3C. J. Lada, J. F. Alves, and M. Lombardi

1. Introduction 32. Measuring Dust Extinction 43. Extinction Mapping of Cloud Cores 64. Extinction Mapping of Cloud Complexes 95. Comparison with Molecular Data 116. Extinction Mapping of Galaxies 137. Concluding Remarks 14

An Observational Perspective of Low-Mass Dense Cores I: Internal Physicaland Chemical Properties 17

J. Di Francesco, N. J. Evans II, P. Caselli, P. C. Myers, Y. Shirley, Y Aikawa, and M. Tafalla1. Introduction and Scope of Review 172. Starless Cores / 183. Density and Temperature Structures 204. Chemical Characteristics 235. Bulk and Turbulent Motions 276. Conclusions 29

An Observational Perspective of Low-Mass Dense Cores II: Evolution Towardthe Initial Mass Function 33

D. Ward-Thompson, P. Andre, R. Crutcher, D. Johnstone, T. Onishi, and C. Wilson1. Introduction 332. Evolutionary Models 353. Observed Core Lifetimes 364. Observations of Magnetic Fields 365. Core Mass Function 386. Cluster-Forming Versus Isolated Cores 397. From Cores to Protostars 418. Discussion and Conclusion 449. Future Developments 44

Extreme Deuteration and Hot Corinos: The Earliest Chemical Signatures ofLow-Mass Star Formation 47

C. Ceccarelli, P. Caselli, E. Herbst, A. G. G. M. Helens, and E. Caux1. Introduction 472. The Physical and Chemical Structure in the First Phases of the Collapse 483. Extreme Deuteration 514. Hot Corinos 545. Chemical Models 556. Conclusions: Closed and Open Questions 58

Molecular Cloud Turbulence and Star Formation 63J. Ballesteros-Paredes, R. S. Klessen, M. -M. Mac Low, and E. Vdzquez-Semadeni

1. Introduction 632. Molecular Cloud Formation 643. Properties of Molecular Cloud Turbulence 664. Properties of Molecular Cloud Cores 695. Control of Star Formation 716. Conclusions 75

Giant Molecular Clouds in Local Group Galaxies 81L. Blitz, Y. Fukui, A. Kawamura, A. Leroy, N. Mizuno, and E. Rosolowsky

1. Introduction 812. The Galaxies 823. Molecular Cloud Properties 864. The Role of Hydrostatic Pressure 895. Beyond the Local Group 906. Star Formation in Extragalactic Giant Molecular Clouds 917. Future Prospects 948. Summary and Conclusions 94

PART II:' STAR FORMATION

Current Advances in the Methodology and Computational Simulation of theFormation of Low-Mass Stars 99

R. I. Klein, S. -I. Inutsuka, P. Padoan, and K. Tomisaka1. Introduction 992. A Brief Survey of Low-Mass Star-Formation Mechanisms 1013. Physical Processes Necessary for Detailed Simulation of Low-Mass Star Formation 1014. Methodology of Numerical Simulations 1045. Recent Simulations and Confrontation with the Observations i; 1086. Summary and Future Directions 113

Stellar Properties of Embedded Protostars 117R. J. White, T. P. Greene, G. W. Doppmann, K. R. Covey, and L. A. Hillenbrand

1. The Discovery and Classification of Protostars 1172. Photospheres and Accretion 1193. Spectroscopic Properties of Protostars Revealed 1214. Implications for Classification Schemes and Formation Theory 1265. Future Prospects 130

The Fragmentation of Cores and the Initial Binary Population 133S. P. Goodwin, P. Kroupa, A. Goodman, and A. Burkert

1. Introduction 1332. The Properties of Multiple Systems '. 1333. The Properties of Prestellar Cores 1394. The Fragmentation of Prestellar Cores 1405. Conclusions 145

The Origin of the Initial Mass Function 149/. A. Bonnell, R. B. Larson, and H. Zinnecker

1. Introduction 1492. Observed Features 1503. Relevant Observational Constraints 1514. Numerical Simulations 1525. Physical Processes 1536. Outstanding Problems 1617. Summary 162

The Formation of Massive Stars 165H. Beuther, E. B. Churchwell, C. F. McKee, and J. C. Tan

1. Introduction 1652. Initial Conditions 1663. High-Mass Protostellar Objects 1684. Feedback Processes 1735. Formation of Star Clusters 1756. Conclusions and Future Prospects 177

Ultracompact HII Regions and the Early Lives of Massive Stars 181M. G. Hoare, S. E. Kurtz, S. Lizano, E. Keto,,and P. Hofner

1. Introduction 1812. Ultracompact Hn Regions 1823. Hypercompact Hn Regions 1894. Future Directions 193

Disks Around Young O-B (Proto)Stars: Observations and Theory 197R. Cesaroni, D. Galli, G. Lodato, C. M. Walmsley, and Q. Zhang

1. Introduction 1972. Observational Aspects , 1983. IRAS 20126+4104: The Prototype Disk : 2044. Formation and Stability of Massive Disks 2055. Disk Lifetime 2086. The Effects of Stellar Companions 2097. Summary and Conclusions 209

PART III: OUTFLOWS

Observations of Jets and Outflows from Young Stars 215J. Bally, B. Reipurth, and C. J. Davis

1. Introduction 2152. Fast Shocks: Observations of Ultraviolet and X-Rays 2163. Visual Wavelength Surveys 2184. Infrared Observations of Molecular Jets 224

Toward Resolving the Outflow Engine: An Observational Perspective 231T. Ray, C. Dougados, F. Bacciotti, J. Eisloffel, and A. Chrysostomou

1. Introduction 2312. Imaging Structures Close to the Jet Base 2323. Kinematics: Velocity Profiles, Rotation, Acceleration, and Implications 2344. Line Diagnostics 2375. Probing the Outflow on AU Scales: Use of Spectroastrometry , 2896. From Brown Dwarfs to Herbig Ae/Be Stars 2407. The Future: Toward Resolving the Central AU 242

XI

Molecular Outflows in Low- and High-Mass Star-forming Regions 245H. G. Arce, D. Shepherd, F. Gueth, C.-F. Lee, R. Bachiller, A. Rosen, and H. Beuther

1. Introduction 2452. General Outflow Properties 2463. Molecular Outflow Models ; 2494. Impact of Outflows on Surrounding Environment 2535. Future Work 257

Jets and Bipolar Outflows from Young Stars: Theory and Observational Tests 261H. Shang, Z.-Y. Li, and N. Hirano

1. Introduction 2612. Thermal-Chemical Modeling of X-Winds 2623. Forbidden Emission Lines 2644. Radio Continuum 2665. Emission from Inner Disk Winds 2686. Inner Disk Winds: Simulation 2687. Signature of Wind Rotation 2698. Dense Core Environment 2709. Molecular Outflows 27110. Concluding Remarks 274

*Disk Winds, Jets, and Outflows: Theoretical and Computational Foundations 277

R. E. Pudritz, R. Ouyed, Ch. Fendt, and A. Brandenburg1. Introduction 2772. Theory of Disk Winds 2783. Simulations: Disks as Jet Engines 2814. Coupled Disk-Jet Evolution 2855. Jets and Star-Disk Interaction 2886. Jets and Gravitational Collapse 291

PART IV: YOUNG STARS AND CLUSTERS

The Rotation of Young Low-Mass Stars and Brown Dwarfs 297W. Herbst, J. Eislbffel, R. Mundt, and A. Scholz

1. Introduction 2972. Observational Methods 2983. Rotation of Young Stellar Objects 2994. Angular Momentum Evolution: Empirical Results 3005. Overview of Variability, Spots, Accretion, and Magnetic Star-Disk Interactions in 305

Young Stellar Objects and Brown Dwarfs6. Interpretations: Comparison of Empirical Results with Theory 307

X-Ray Properties of Young Stars and Stellar Clusters 313E. Feigelson, L. Townsley, M. Gtidel, and K. Stassun

1. Introduction 3132. Flaring in Pre-Main-Sequence Stars 3143. The Evolution of Magnetic Activity 3194. X-Ray Stars and Hot Gas in Massive Star-forming Regions 3215. X-Ray Effects on Star and Planet Formation 3236. Summary 325

The Taurus Molecular Cloud: Multiwavelength Surveys with XMM-Newton,the Spitzer Space Telescope, and the Canada-France-Hawaii Telescope 329

M. Giidel, D. L. Padgett, and C. Dougados1. Introduction 3292. New Surveys of the Taurus Clouds 3313. Survey Strategies and Status 3334. Overview of the Population 3355. The Substellar Sample 3366. X-Rays and Magnetic Activity 3397. Jets and Outflows 3418. Summary 343

The Low-Mass Populations in OB Associations 345C. Briceno, T. Preibisch, W. H. Sherry, E. A. Mamajek, R. D. Mathieu, F. M. Walter,and H. Zinnecker

1. Introduction 3452. Searches for Low-Mass Pre-Main-Sequence Stars in OB Associations 3473. Ages and Age Spreads of Low-Mass Stars 3504. The Initial Mass Function in OB Associations 3515. Disk Evolution 3536. The Origin of OB Associations: Bound Versus Unbound Stellar Groups 3557. Constraints on Rapid and Triggered/Sequential Star Formation 3568. Concluding Remarks 357

The Structure and Evolution of Young Stellar Clusters 361L. Allen, S. T. Megeath, R. Gutermuth, P. C. Myers, S. Wolk, F. C. Adams, J. Muzerolle,E. Young, and J. L. Pipher

1. Introduction 3612. Methods of Identifying Young Stars in Clusters 3623. The Structure and Evolution of Clusters: Observations 3654. Gas Disruption and the Lifetime of Embedded Clusters '.-. 3705. Early Cluster Evolution 3726. Effects of Clusters on Star and Planet Formation 3727. Conclusions 374

PART V: YOUNG BINARIES — BROWN DWARFS

New Observational Frontiers in the Multiplicity of Young Stars 379G. Duchene, E. Delgado-Donate, K. E. Haisch Jr., L. Loinard, and L. F. Rodriguez

1. Introduction 3792. An Update on the Multiplicity of Young Low-Mass Stars 3803. Embedded Multiple Protostars 3824. Core Fragmentation and Early Dynamical Evolution of Multiple Systems 3885. Conclusions and Perspectives 392

Disk Evolution in Young Binaries: From Observations to Theory 395J.-L. Monin, C. J. Clarke, L. Prato, and C. McCabe

1. Introduction 3952. Inner Disk Diagnostics in Young Binaries 3963. Disk Structure in Young Binaries 3984. Disk Evolution in Young Binaries 4015. Future Directions 407

Xlll

Dynamical Mass Measurements of Pre-Main-Sequence Stars: FundamentalTests of the Physics of Young Stars 411

R. D. Mathieu, I. Baraffe, M. Simon, K. G. Stassun, and R. White1. Introduction 4112. Dynamical Mass Measurements 4123. Comparisons of Dynamical Masses with Pre-Main-Sequence Stellar Evolution Models 4154. Theoretical Models of Pre-Main-Sequence Stellar Evolution 4195. Visions of the Future 424

Not Alone: Tracing the Origins of Very-Low-Mass Stars and Brown DwarfsThrough Multiplicity Studies 427

A. J. Burgasser, I. N. Reid, N. Siegler, L. Close, P. Allen, P. Lowrance, and J. Gizis1. Introduction 4272. Observations of Very-Low-Mass Binaries 4293. Confronting the Models 4364. Future Observational Directions 438

The Formation of Brown Dwarfs: Observations 443K. L. Luhman, V. Joergens, C. Lada, J. Muzerolle, I. Pascucci, and R. White

1. Introduction 4432. Initial Mass Function , 4443. Kinematics and Positions at Birth 4454. Multiplicity 4455. Accretion 4486. Circumstellar Disks 4507. Summary 454

The Formation of Brown Dwarfs: Theory 459A. Whitworth, M. R. Bate, A. Nordlund, B. Reipurth, and H. Zinnecker

1. Introduction 4592. Evidence that Brown Dwarfs form like Low-Mass Hydrogen-burning Stars 4603. Star-Formation Thermodynamics 4624. Forming Very-Low-Mass Prestellar Cores in Turbulent Clouds 4665. Collapse and Fragmentation of Large Prestellar Cores 4686. Disk Fragmentation 4697. Premature Ejection of Protostellar Embryos 4708. Photoerosion of Pre-Existing Cores 4729. Simulations of Cluster Formation by Turbulent Cloud Collapse 47310. Conclusions 474

PART VI: CIRCUMSTELLAR DISKS

Magnetospheric Accretion in Classical T Tauri Stars 479J. Bouvier, S. H. P. Alencar, T. J. Harries, C. M. Johns-Krull, and M. M. Romanova

1. The Magnetic Accretion Paradigm 4792. Magnetic Field Measurements 4803. Spectral Diagnostics of Magnetospheric Accretion 4854. Observational Evidence for Magnetospheric Accretion 4875. Numerical Simulations of Magnetospheric Accretion 4896. Conclusions 492

Interferometric Spectroimaging of Molecular Gas in Protoplanetary Disks 495A. Dutrey, S. Guilloteau, and P. Ho

1. Introduction 4952. Molecular Line Formation and Disk Models 4963. Protoplanetary Disk Properties 5004. Some Interesting Case Studies 5015. Molecular Chemistry in Disks 5046. Summary and Perspectives 505

Gaseous Inner Disks 507J. R. Najita, J. S. Carr, A. E. Glassgold, and J. A. Valenti

1. Introduction 5072. Observations of Gaseous Inner Disks 5093. Thermal-Chemical Modeling 5144. Current and Future Directions 5185. Summary and Conclusions 520

Multiwavelength Imaging of Young Stellar Object Disks: Toward an Understandingof Disk Structure and Dust Evolution 523

A. M. Watson, K. R. Stapelfeldt, K. Wood, and F. Menard1. Introduction 5232. Observational Progress 5243. Modeling Techniques 5284. Disk Structure from Scattered-Light Images 5295. Highlights of Applied Disk Modeling 5326. Prospects for Future Advances 535

The Circumstellar Environments of Young Stars at AU Scales 539R. Millan-Gabet, F Malbet, R. Akeson, C. Leinert, J. Monnier, and R. Waters

1. Introduction 5392. The Inner Disk ; 5413. The Outer Disk ': 5454. Other Phenomena 5475. Summary and Open Questions 5496. Future Prospects 550

Models of the Structure and Evolution of Protoplanetary Disks 555C. P. Dullemond, D. Hollenbach, I. Kamp, and P. D 'Alessio

1. Introduction 5552. Formation and Viscous Evolution of Disks 5553. Vertical Structure of Dusty Disks 5574. Gas Temperature and Line Spectra 5625. Photoevaporation of a Disk by Its Central Star 5656. Summary and Outlook 569

Evolution of Circumstellar Disks Around Normal Stars: Placing OurSolar System in Context 573

M. R. Meyer, D. E. Backman, A. J. Weinberger, and M. C. Wyatt1. Introduction 5732. Evolution of Circumstellar Disks 5743. Physical Properties of Individual Systems 5764. Overview of Debris Disk Models 5795. Comparison to our Solar System 5836. Summary and Implications for Future Work .- 585

PART VII: PLANET FORMATION ANDEXTRASOLAR PLANETS

Formation of Giant Planets 591J. J. Lissauer and D. J. Stevenson

1. Introduction 5912. Models of Giant Planets 5933. Giant Planet Formation Models 5974. Outstanding Questions 6045. Summary 604

Gravitational Instabilities in Gaseous Protoplanetary Disks and Implicationsfor Giant Planet Formation 607

R. H. Durisen, A. P. Boss, L. Mayer, A. F. Nelson, T Quinn, and W. K. M. Rice1. Introduction 6072. Physics of Gravitational Instabilities 6073. Numerical Methods 6104. Key Issues 6125. Interactions with Solids 6186. Planet Formation 619

4

Gaseous Planets, Protostars, and Young Brown Dwarfs: Birth and Fate 623G. Chabrier, I. Baraffe, F Selsis, T. S. Barman, P. Hennebelle, and Y. Alibert

1. Introduction 6232. Gaseous Planets: Birth and Evolution 6243. Gravitational Collapse of Prestellar Cores 6284. Effect of Accretion on the Early Evolution of Low-Mass Objects 6315. Brown Dwarf Versus Planet: Observable Signatures 6346. Conclusion 635

The Diverse Origins of Terrestrial-Planet Systems 639M. Nagasawa, E. W. Thommes, S. J. Kenyon, B. C. Bromley, and D. N. C. Lin

1. Introduction 6392. Background 6393. Evolution to Chaotic Growth 6424. New Simulations of Chaotic Growth 6445. Conclusion and Implications 652

Disk-Planet Interactions During Planet Formation 655J. C. B. Papaloizou, R. P. Nelson, W. Kley, F. S. Masset, and P. Artymowicz

1. Introduction 6552. Type I Migration 6563. Type II Migration 6594. Type III Migration 6615. Turbulent Protoplanetary Disks 6646. Summary and Discussion 667

xvi

Planet Migration in Planetesimal Disks 669H. F. Levison, A. Morbidelli, R. Gomes, and D. Backman

1. Introduction 669'. 2. Basic Principles of Simple Migration 670

3. Resonant Capture During Planet Migration 6724. Simple Migration in the Solar System 6735. Dynamical Instabilities as a Migration Process 675

( 6. The Nice Model of the Early Dynamical Evolution of the Giant Planets 6767. Migration in Extrasolar Planetesimal Disks 6798. Caveats and Limitations of Numerical Simulations 6829. Closing Comments 683

' A Decade of Radial-Velocity Discoveries in the Exoplanet Domain 685S. Udry, D. Fischer, and D. Queloz

1. Introduction 6852. Orbital Properties of Exoplanets 685

' 3. The Quest for Very High Precision 6904. Multiple Planet Systems 6925. Primary Star Properties 6946. Followup of Transiting Planets 6967. The Future of Radial Velocities 697

When Extrasolar Planets Transit Their Parent Stars 701D. Charbonneau, T. M. Brown, A. Burrows, and G. Laughlin

1. Overview 701j 2. Physical Structure 702: 3. Atmospheres 710! 4. Future Prospects 713

j Direct Detection of Exoplanets 717] J. -L. Beuzit, D. Mouillet, B. R. Oppenheimer, and J. D. Monnier \j 1. Introduction 717j 2. Science : 718| 3. High-Contrast Imaging 7211 4. Interferometry 725

Atmospheres of Extrasolar Giant Planets : 733M. S. Marley, J. Fortney, S. Seager, and T. Barman

1. Introduction 7332. Overview of Giant Planet Atmospheres 7333. Model Atmospheres 7374. Observations of Hot Jupiters 7435. The Future 746

PART VIII: DUST, METEORITES, ANDTHE EARLY SOLAR SYSTEM

The Chemical Evolution of Protoplanetary Disks 751E. A. Bergin, Y. Aikawa, G. A. Blake, and E. F. van Dishoeck

1. Introduction 7512. General Theoretical Picture 7523. Observations 7554. Chemical and Physical Links > 7575. Deuterated Species in Disks and Comets 7626. Outstanding Issues and Future Prospects 764

Dust in Protoplanetary Disks: Properties and Evolution 767A. Natta, L. Testi, N. Calvet, Th. Henning, R. Waters, and D. Wilner

1. Introduction 7672. Grain Growth: Why and How 7683. Observational Techniques 7694. The Smallest Particles: Polycyclic Aromatic Hydrocarbons 7705. From Submicrometer- to Micrometer-sized Grains 7716. Growth to Centimeter-sized Grains 7737. Mineralogy 7758. Summary and Open Problems 777

Growth of Dust as the Initial Step Toward Planet Formation 783C. Dominik, J. Blum, J. N. Cuzzi, and G. Wurm

1. Introduction 7832. Dust Aggregation Experiments and Theory 7843. Particle-Gas Interaction 7894. Global Disk Models with Settling and Aggregation 7945. Summary and Future Prospects 797

Astronomical and Meteoritic Evidence for the Nature of Interstellar Dustand Its Processing in Protoplanetary Disks.* 801

C. M. O'D. Alexander, A. P. Boss, L. P. Keller, J. A. Nuth, and A. Weinberger1. Introduction 8012. Circumstellar, Interstellar, and Protoplanetary Dust 8023. Condensation, Irradiation, and Annealing of Dust Analogs 8034. Evidence for Thermal Processing of Dust in Meteorites and Interplanetary

Dust Particles 8045. Modeling of Grain Heating in Protoplanetary Disks 8106. Summary 810

Comet Grains and Implications for Heating and Radial Mixing in the \Protoplanetary Disk 815

D. Wooden, S. Desch, D. Harker, H.-P Gail, and L. Keller1. Introduction 8162. Comet Grains and Anhydrous Chondritic Porous Interplanetary Dust Particles 8173. Forming Magnesium-rich Crystals in Disks 8234. Grain Heating and Radial Mixing in Disks 8265. Conclusions: Constraints on Transient Heating Events Provided by

Cometary Grains 830

From Dust to Planetesimals: Implications for the Solar Protoplanetary Disk fromShort-lived Radionuclides 835

M. Wadhwa, Y. Amelin, A. M. Davis, G. W. Lugmair, B. Meyer, M. Gounelle,and S. J. Desch

1. Introduction 8362. Short-lived Radionuclides in the Early Solar System: The Latest Results 8363. Sources of Short-lived Radionuclides and Their Implications 8384. Astrophysical Setting of the Solar Protoplanetary Disk 8415. From Dust to Planetesimals 8426. Outlook and Final Remarks 845

xvm

Origin and Evolution of Oxygen-Isotopic Compositions of the Solar System 849H. Yurimoto, K. Kuramoto, A. N. Krot, E. R. D. Scott, J. N. Cuzzi, M. H. Thiemens,and J. R. Lyons

1. Introduction 8492. Chondrites and Their Components 8503. Oxygen-Isotopic Compositions of Chondritic Components 8514. Bulk Oxygen-Isotopic Compositions of Chondrites and Achondrites 8515. Oxygen-Isotopic Composition of the Sun 8526. Origin of Oxygen-Isotopic Anomaly in the Solar System 8527. Self-shielding of Carbon Monoxide in Molecular Clouds 8538. Evolution of Protoplanetary Disks and Oxygen Isotopes 8559. Future Work 860

Water in the Small Bodies of the Solar System 863D. Jewitt, L. Chizmadia, R. Grimm, and D. Prialnik

1. Introduction 8632. Evidence from the Meteorites 8643. Astronomical Evidence 8674. Isotopic Evidence 8715. Thermal Evolution of Small Bodies 8726. Summary 877

Physical Properties of Transneptunian Objects 879D. P. Cruikshank, M. A. Barucci, J. P. Emery, Y. R. Fernandez, W. M. Grundy, K. S. Noll,and J. A. Stansberry

1. Introduction 8792. Colors and Taxonomy 8803. Spectroscopy (0.3-5 Micrometers) 8814. Thermal Infrared Spectroscopy 8835. Models of Planetary Surfaces 8846. Sizes and Albedos of Transneptunian Objects 8877. Multiplicity in the Kuiper Belt 8888. Summary and Conclusions 891

A Brief History of Transneptunian Space 895E. Chiang, Y. Lithwick, R. Murray-Clay, M. Buie, W. Grundy, and M. Holman

1. Introduction ; 8952. The Kuiper Belt Observed Today 8963. Theoretical Timeline 9004. Directions for Future Work 909

PART IX: LIFE

Comparative Planetology and the Search for Life Beyond the Solar System 915C. A. Beichman, M. Fridlund, W. A. Traub, K. R. Stapelfeldt, A. Quirrenbach,and S. Seager

1. Studies of Planetary Systems and the Search for Life 9152. Transiting Planets 9173. Astrometry 9184. Coronagraphy 9205. Interferometry 9216. Synergy Among Techniques for Nearby Planets 9227. Target Stars .' 9248. Discussion and Conclusions 926

xix

From Protoplanets to Protolife: The Emergence and Maintenance of Life 929E. Gaidos and F. Selsis

1. Introduction 9292. When and Where Did Life Emerge? 9303. Elements of Habitability 9354. Extrasolar Earths and Other Origins 939

Color Section following page 944

Index 945