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

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Presentation on theme: "Structure & Evolution of Protoplanetary Disks: Merging 3D Radiation Transfer & Hydrodynamics Kenneth Wood St Andrews."— Presentation transcript:

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

2 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 DataTheory Radiation Transfer Models & Observational Signatures

3 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

4 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)

5 Star Formation Theory Class 0Class IClass II

6 Star Formation: Observations 1 1000 10100 ( m) 1 1000 101001 1000 10100 F Bourke 2001 Padgett et al. 1999 Krist et al. 2000 BHR71TW HydraeIRAS 04302+2247 0III

7 Near-IR HST Images

8 Disks, Disks, Disks…

9 T Tauri Accretion Disks: Images Disk density: hydrostatic flared disk: h / r = c s (r) / (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 i = 25i = 75i = 85 400 AU

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

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

12 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

13 HH 30 IRS Accretion Disk Burrows et al. 1996 HST WFPC2: Green:F555W (V Band) Red:F617N (H, 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

14 HH 30 IRS: Disk Geometry HST WFPC2 Model Hydrostatic flared disk, i = 84 Dust + gas suspended above midplane Consistent with T(r), (r) for irradiated disks (DAlessio et al. 1999)

15 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 (0.55 m)I (0.85 m)K (2.25 m)

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

17 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 ( ~ M) M d ~ 2 * 10 -3 M Wood et al. 2002

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

19 HH 30 IRS: Image Variability

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

21 Magnetic Accretion in HH 30 IRS Wood & Whitney 1998

22 Magnetic Accretion in HH 30 IRS T * =3500K; T s =10000K; A ~ 6% Asymmetric brightening; V ~ 1.5m Photometric centroid shift: ~ 0.5 Wood & Whitney 1998 Stapelfeldt et al. 1999

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

24 GM Aur: Disk/Planet Interaction? NICMOS coronagraph Scattered light modeling: M disk ~ 0.04 M ; R disk ~ 300 AU; i ~ 50 Schneider et al. 2002 1200 AU

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

26 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

27 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

28 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

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

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

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

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

33 Color Evolution Wood et al. 2001

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

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

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

37 Space Infrared Telescope SIRTF: launch in January 2003 Lots of data: 6 Legacy programs Infrared spectra for 3 m < < 160 m Study disks: environments and ages Website with grid of models

38 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

39 Disk Temperature Structure Stellar photons absorbed at ~ 4 h(r) above midplane Iterate with dynamics Self-consistent disk structure 6 AU20 AU300 AU T 1/5

40 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

41 Monte Carlo Photoionization T * = 40000 K Q(H 0 ) = 4.26 10 49 s -1 n(H) = 100 cm -3 Calculate 3D ionization structure Study percolation of ionizing photons in fractal ISM

42 Stromgren Volume in a Dickey-Lockman Disk 2 Kpc n(H 0 )Ionization fraction f ~ 10 -3 Q(H 0 ) = 2 10 50 s -1 : Escape fraction = 22% Ionization of HVCs, Magellanic Stream, IGM…

43 3D Stromgren Volumes n(H 0 ) (before)Ionization fractionn(H 0 ) (after) Clumpy density; 2 sources with Q(H 0 ) = 2 10 50 s -1 3D ionization structure, shadow regions


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