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Monte Carlo Radiation Transfer in Protoplanetary Disks: Disk-Planet Interactions. Kenneth Wood St Andrews. Radiation Transfer + Hydrodynamics. RT Models: Barbara Whitney, Jon Bjorkman, Christina Walker, Mark O’Sullivan Dust Theory: Mike Wolff
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Monte Carlo Radiation Transfer in Protoplanetary Disks:Disk-Planet Interactions Kenneth Wood St Andrews
Radiation Transfer + Hydrodynamics RT Models: Barbara Whitney, Jon Bjorkman, Christina Walker, Mark O’Sullivan Dust Theory: Mike Wolff SPH Models: Ken Rice, Mike Truss, Ian Bonnell Observations: Rachel Akeson, Charlie Lada, Ed Churchwell, Glenn Schneider, Angela Cotera, Keivan Stassun
Monte Carlo Development History • Scattered light disks & envelopes (1992) • 3D geometry & illumination (1996) • Dust radiative equilibrium (2001) SEDs disks + envelopes • Monte Carlo for disk surface + diffusion for interior (2002) • Density grids from SPH simulations (2003) • Spatial variation of dust opacity (2003) • Self consistent vertical hydrostatic equilibrium (2004) 1992: Predictions 1996: HST data GM Aur: 4AU gap, disk-planet interaction
Disk Structure Calculations • Our models used parameterized disks: power laws for S(r), h(r) • Disk theory: reduce model parameter space • Irradiated accretion disks: S ~ r -1, h ~ r1.25 (D’Alessio, Calvet, & collaborators) • New Monte Carlo: iterate for disk structure (Walker et al. 2004) • Model disk-planet interactions in GM Aur
Disk-Planet Interactions: Gap Clearing • Observational signatures: images, SEDs? Simulation from Ken Rice & Phil Armitage Papaloizou, Lin, Bodenheimer, Lubow, Artymowicz, Nelson, D’Angelo, Kley, …
700mm 700mm ALMA simulation Wolf et al. 2002 Protoplanetary Disks • Need high resolution imaging: ALMA • Gap clearing simulation images:
Rin = 7R* Rin = 4 AU GM Aur Inner Gaps from SED Modeling • Remove inner disk material: redistribute near-IR excess emission to longer ls Rice et al. (2003) See also: Dullemond, et al. Calvet, D’Alessio
T 6 AU 20 AU 300 AU r1/5 GM Aur Estimating Rin from SEDs • Hot inner edge emits in IR • Include inner edge emission when estimating Rin
GM Aur Monte Carlo, Rin = 4 AU, i = 0 - 50 CG97, Rin = 0.1 AU CG97, Rin = 4 AU Vertical Hydrostatic Equilibrium
ISM Disk dust Disk Dust: Grain Growth Dust Size Distribution: Power law + exponential decay Grain sizes in excess of 50mm Grayer opacity compared to ISM Fits HH30, GM Aur, AA Tau, … Opacity slopes: Dust model: ksub-mm ~ l-0.8; kB/kK ~ 2.5 Beckwith & Sargent (1991): sub-mm continuum SEDs: k ~ l-1 Watson & Stapelfeldt (2004): HH 30 IRS: kB/kK ~ 1.5 – 4.5
1200 AU GM Aur: Disk/Planet Interaction? Schneider et al. 2003 • NICMOS coronagraph • Scattered light modeling: • Mdisk ~ 0.04 M8; Rdisk ~ 300 AU; i ~ 50
GM Aur: Disk/Planet Interaction? • Tiny near-IR excess: inner hole first suggested by Koerner, Sargent, & Beckwith (1993) • SED model requires 4AU gap: planet?
GM Aur: Disk/Planet Interaction? • 3D SPH calculation from Ken Rice • Planet at 2.5AU clears inner 4AU in ~2000 yr Rice et al. 2003
GM Aur: Disk/Planet Interaction? • Higher mass “planets”: sharper truncation Rice et al. 2003
GM Aur: Disk/Planet Interaction? • Spitzer SED can discriminate “planet” mass • Centroid shifting ~ 0.1mas: Keck, SIM? Mp = 2MJ Mp = 50MJ Rice et al. 2003
GM Aur DM Tau Lk Ca 15 TW Hya More Disks with Gaps • IRTF: Bergin, Calvet, Sitko, et al. (2004) • Gap sizes: 3 AU < Rgap < 7 AU • Silicate emission: smaller grains in inner disk • Sharp truncation, very low density inner disks
GM Aur: 6.5 AU Gap • SED model requires low density material in cleared region • Inner disk mass ~ 10-8M8 • High resolution imaging of inner holes…?
T r1/5 GM Aur: 6.5 AU Gap • Inner disk mass ~ 10-8M8
2mm 8mm 170mm • Low density material in gap “fills in” images • Inner gaps more obvious in SEDs !!
Summary & Future Research • Monte Carlo: self-consistent disk structure calculations • GM Aur: Disk-planet interaction, need mid-IR data • Direct imaging of inner gaps: low density material “fills in” surface brightness => SEDs find gaps! • Coding: Radiation pressure Include gas opacity Transiently heated grains • Goal: merge radiation transfer & hydro • Codes now available at: http://gemelli.spacescience.org/~bwhitney/codes