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Structure & Evolution of Protoplanetary Disks:Merging 3D Radiation Transfer & Hydrodynamics: 

Structure & Evolution of Protoplanetary Disks: Merging 3D Radiation Transfer & Hydrodynamics Kenneth Wood St Andrews

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Data: Imaging polarimetry Photometric monitoring Scattered light images Spectral energy distributions (SEDs) Theory: Dynamical models of star formation: Collapsing clouds, jets, accretion disks, debris disks, & planet formation RT Models: 3D Monte Carlo techniques

Friends & Collaborators: 

Friends & Collaborators RT Models & Dust Theory: Barbara Whitney, Jon Bjorkman, Mike Wolff Dynamical Models: Ken Rice, Ian Bonnell, Phil Armitage, Matthew Bate, Scott Kenyon, Adam Frank Observations: Charlie Lada, Ed Churchwell, Anneila Sargent, Glenn Schneider, Angela Cotera, Debbie Padgett, Keivan Stassun

Monte Carlo Capabilities: 

Monte Carlo Capabilities 3D geometry & illumination Incorporate MHD density & velocity grids Scattered light images (optical & infrared) Radiative equilibrium dust temperatures SEDs & thermal imaging (mid-IR, sub-mm)

Star Formation Theory: 

Star Formation Theory Class 0 Class I Class II

Star Formation: Observations: 

Star Formation: Observations l(mm) Bourke 2001 Padgett et al. 1999 Krist et al. 2000 BHR71 TW Hydrae IRAS 04302+2247 “0” “I” “II”

Near-IR HST Images: 

Near-IR HST Images

Disks, Disks, Disks…: 

Disks, Disks, Disks…

T Tauri Accretion Disks: Images: 

T Tauri Accretion Disks: Images Disk density: hydrostatic flared disk: h / r = cs(r) / W(r) Shakara & Sunyaev (1973), Lynden-Bell & Pringle (1974) Direct starlight 10,000 brighter than scattered light from disk Best detected when star occulted by edge-on flaring disk Whitney & Hartmann 1992

T Tauri Accretion Disks: SEDs: 

T Tauri Accretion Disks: SEDs Pole-on: Large IR excess Edge-on: Double peaked SED: scattered light + thermal Wood et al. 2002

Star Formation in Taurus: 

Star Formation in Taurus © Steve Kohle & Till Credner, AlltheSky.com

L1551 Region: 

L1551 Region Whitney, Gomez, & Kenyon (Mt Hopkins, 48”) Red = [S II] White = Visual L1551 IRS5 HL Tau XZ Tau HH 30 HH 30 IRS 1’ = 8400AU

HH 30 IRS Accretion Disk: 

HH 30 IRS Accretion Disk Burrows et al. 1996 HST WFPC2: Green: F555W (V Band) Red: F617N (Ha, S[II]) Scattered light models: Assume ISM dust opacity Image morphology: disk geometry, inclination Width of dust lane: optical depth, disk mass Bacciotti et al. 1999

HH 30 IRS: Disk Geometry: 

HH 30 IRS: Disk Geometry HST WFPC2 Model Hydrostatic flared disk, i = 84 Dust + gas suspended above midplane Consistent with T(r), S(r) for irradiated disks (D’Alessio et al. 1999)

Multiwavelength Models: 

Multiwavelength Models ISM Dust: Opacity decreases by 10 from V to K Dust lane width decreases into IR Very compact nebulosity at K Wood et al. 1998 V (0.55mm) I (0.85mm) K (2.25mm)

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Cotera et al. 2001 V (0.55mm) I (0.85mm) K (2.25mm) NICMOS: Wide dust lane at K Circumstellar dust is GRAYER than ISM dust Grain Growth in disk

HH 30 IRS: SED Models: 

HH 30 IRS: SED Models Model: Geometry from HST images; Heating: starlight + accretion Model HST images and SED: Determine dust size distribution Find: Grayer opacity Optical opacity < ISM Larger disk mass (t ~ kM) Md ~ 2 * 10-3 M8 Wood et al. 2002

HH 30 IRS: Grain Growth: 

HH 30 IRS: Grain Growth ISM HH 30 IRS Dust Size Distribution: Power law + exponential decay Grain Sizes in excess of 50mm Grayer opacity, Sub-mm slope ~ 1/l Beckwith & Sargent (1991): sub-mm continuum SEDs: k ~ 1/l

HH 30 IRS: Image Variability: 

HH 30 IRS: Image Variability

Magnetic Accretion in HH 30 IRS: 

Magnetic Accretion in HH 30 IRS Stellar B-field not aligned with rotation axis Truncates disk, accretion along field lines Hot Spots on star at magnetic poles UV excess, photometric modulation Ghosh & Lamb1979 Shu et al. 1994

Magnetic Accretion in HH 30 IRS: 

Magnetic Accretion in HH 30 IRS Wood & Whitney 1998

Magnetic Accretion in HH 30 IRS: 

Magnetic Accretion in HH 30 IRS T*=3500K; Ts=10000K; DA ~ 6% Asymmetric brightening; DV ~ 1.5m Photometric centroid shift: d ~ 0.5’’ Wood & Whitney 1998 Stapelfeldt et al. 1999

HH 30 IRS: Photometry: 

HH 30 IRS: Photometry DV ~ 1.5mag, DT ~ days: Typical of CTTs, accretion hot spots Variability all due to scattered light Wood et al. 2000

GM Aur: Disk/Planet Interaction?: 

GM Aur: Disk/Planet Interaction? NICMOS coronagraph Scattered light modeling: Mdisk ~ 0.04 M8; Rdisk ~ 300 AU; i ~ 50 Schneider et al. 2002

GM Aur: Disk/Planet Interaction?: 

GM Aur: Disk/Planet Interaction? No near-IR excess SED model requires 4AU gap: planet? Lin & Papaloizou; Seyer & Clarke; Nelson, etc

GM Aur: Disk/Planet Interaction?: 

GM Aur: Disk/Planet Interaction? 3D SPH calculation from Ken Rice Planet at 2.5 AU clears disk out to 4AU Rice et al. 2002

GM Aur: Disk/Planet Interaction?: 

GM Aur: Disk/Planet Interaction? 3D SPH calculation from Ken Rice Planet at 2.5 AU clears disk out to 4AU Rice et al. 2002

GM Aur: Disk/Planet Interaction?: 

GM Aur: Disk/Planet Interaction? 3D SPH density grid into Monte Carlo code SIRTF SED can discriminate planet mass Centroid shifting ~ 0.1mas: Keck, SIM? Rice et al. 2002

Disk Evolution: 

Disk Evolution Lada et al. 2000 Trapezium Cluster IR-EXCESS = DISKS Cluster age ~ 1.5Myr Disk Frequency: 80%

Disk Lifetimes: 

Disk Lifetimes Haisch et al. 2000 CLUSTER SURVEYS: Disk frequency declines with cluster age Disk Lifetime: ~ 6Myr

Disk Evolution: 

Disk Evolution Disk structure does not change Disk mass decreases homologously Mass = mass of dust contributing to SED What Md can near-IR surveys detect? Observables: SEDs, colors Current evidence for disk mass evolution?

SED Evolution: 

SED Evolution d = 500pc; 10-8 M8 < Md < 10-1 M8 SIRTF 5s, 500secs Wood et al. 2002

Color Evolution: 

Color Evolution Wood et al. 2001

Observing Disk Evolution: 

Observing Disk Evolution JHKL surveys: disk frequency & lifetime JHKL surveys: detect Md > 10-7M8 Far-IR & (sub)mm: disk mass evolution Mid-IR (10mm & 25mm): disk mass evolution

Taurus-Auriga Sources: 

Taurus-Auriga Sources Gap in K-N distribution: transition from disks to no disks Kenyon & Hartmann 1995 * = I + = II ( = III

Disk Masses in Taurus-Auriga: 

Disk Masses in Taurus-Auriga Evolution models: disk clearing rapid for Md < 10-6 M8 Wood et al. 2002 1 = 10-1 M8 2 = 10-2 M8 3 = 10-3 M8 etc

Space Infrared Telescope: 

Space Infrared Telescope SIRTF: launch in January 2003 Lot’s of data: 6 Legacy programs Infrared spectra for 3mm < l < 160mm Study disks: environments and ages Website with grid of models

Feedback in Star Formation: 

Feedback in Star Formation HH 30 IRS, GM Aur: Signatures of magnetic accretion & SPH models Bigger Goal: Combine RT and hydro simulations Temperature, radiation pressure & ionization structure

Disk Temperature Structure: 

Disk Temperature Structure Stellar photons absorbed at ~ 4 h(r) above midplane Iterate with dynamics Self-consistent disk structure

Summary & Future Research: 

Summary & Future Research Disk Structure & Variability: HH 30, GM Aur Model data with analytic density structures Now testing hydro simulations SIRTF: characterize large numbers of disks Goal: merge radiation transfer & hydro

Monte Carlo Photoionization: 

Monte Carlo Photoionization Calculate 3D ionization structure Study percolation of ionizing photons in fractal ISM

Stromgren Volume in a Dickey-Lockman Disk: 

Stromgren Volume in a Dickey-Lockman Disk 2 Kpc n(H0) Ionization fraction f ~ 10-3 Q(H0) = 2 1050 s-1: Escape fraction = 22% Ionization of HVCs, Magellanic Stream, IGM…

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3D Stromgren Volumes n(H0) (before) Ionization fraction n(H0) (after) Clumpy density; 2 sources with Q(H0) = 2 1050 s-1 3D ionization structure, shadow regions