1 / 46

T Tauri and Debris Disks

T Tauri and Debris Disks. Protostars & Planets IV, Mannings, Boss & Russell eds. B. Zuckerman, ARAA 2001, 39: 549 W-F Thi 2002, PhD thesis, Leiden G-J van Zadelhoff 2002, PhD thesis, Leiden. Rene´ Liseau. Pawel Artymowicz Alexis Brandeker Malcolm Fridlund Göran Olofsson.

husher
Download Presentation

T Tauri and Debris Disks

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. T Tauri and Debris Disks Protostars & Planets IV,Mannings, Boss & Russell eds. B. Zuckerman, ARAA 2001, 39: 549 W-F Thi 2002, PhD thesis, Leiden G-J van Zadelhoff 2002, PhD thesis, Leiden Rene´ Liseau Pawel Artymowicz Alexis Brandeker Malcolm Fridlund Göran Olofsson

  2. Disks in Time I. Kant 1755 Allgemeine Naturgeschichte und Theorie des Himmels P.S. Laplace 1796, 1799 Exposition du systeme du monde Mechanique celeste

  3. Disks in Time JE Keeler 1895 ApJ 1: 416

  4. Disks in Time IRAS 1983 HST 1993 ISO 1995 T Tauri Disks: around young stars (0.1 - 10 Myr) of half a solar mass (0.1 - 1 Msun) at 150 pc distance (50 - 450 pc) in and/or near molecular clouds ``accretion disks´´ Debris Disks: around young MS-stars (10 - 400 Myr) of about a solar mass (1 - 2 Msun) at 20 pc distance (3 - 70 pc) in the general field ``Vega-excess stellar disks`´

  5. Frequency of Disks High Rate of occurence around young stars NGC 2024 86% Trapezium cluster 80% IC 348 65% Haisch et al. 2001 BDs in Trapezium cluster 65% Muench et al. 2001

  6. Disk Images

  7. T Tauri Disk with Jet HH 30 in L 1551 (Taurus)

  8. T Tauri Disks - Sizes R=7000 AU Fridlund et al. 2002 (mm line data - single dish) White et al. 2000 (mid- & far IR line + cont. - ISO) L 1551 IRS5 outflow source

  9. T Tauri Disks - Sizes Fridlund et al. 2002 • Size scale (AU) Tracer (mode) Reference • 20000 CS (1- 0) (S) Kaifu et al. 1984 • 5000 - 10000 13CO (1- 0) (S) Fridlund et al. 1989 • 1400 C18O (1- 0) (I) Sargent et al. 1988 • <500 1.4 mm (I) Woody et al. 1989 • 45 + 1600 mm, cm (I) Keene & Masson 1990 • 200 0.8 mm (I) Lay et al. 1994 • 7000 H13CO+ (1- 0) (S) Mizuno et al. 1994 • 5000 0.7 - 1 mm (S) Ladd et al. 1995 • 4000 - 6000 C18, 17O (2- 1) (S) Fuller et al. 1995 • 1200 13CO (1- 0) (I) Ohashi et al. 1996 • 4000 H13CO+ (1- 0) (I) Saito et al. 1996 • 5000 H12, 13CO+ (1- 0) (S, I) Hogerheijde et al.1997, 98 • 2500 C18O+ (1- 0) (I) Momose et al. 1998 Size depends on frequency/mode of observation

  10. T Tauri Disks - Sizes Two Disks: separation = 40 AU & R = 5 AU Rodriguez et al. 1998 (7 mm cont. - VLA Interferometer ) L 1551 IRS5 outflow source

  11. T Tauri Disks - Sizes Summarising: T Tauri/HABE disks 50 - 100 AU Dust: mm-continuum interferometry 100 - 300 AU Dust: scattered stellar light 300 AU Gas: CO lines (evidence for Kepler rotation) Silhouettte disks (``proplyds´´) up to 1000 AU Dust: scattered stellar light

  12. T Tauri Disks - Sizes & Masses

  13. T Tauri Disks - Masses Lower limit: 0.001 to 1 MSun (mm/submm continuum) How good are these numbers? Do we understand disks?

  14. T Tauri Disks - Masses Assume optically thin emission at long wavelengths (mm+) monochromatic flux Fn ~ kn T spherical dust grains in equilibrium with stellar radiation achieve T(a, R) = (h/k) p1/(4+b) (L/a R2)1/(4+b) Qabs(n)/a = Q0nb p = (Qvis/Q0) c2/(32p2 h (3+b)! Sm m–(4+b) ) i.e. T ~ R-2/(4+b) b = 0 => T ~ R-0.50 b = 1 => T ~ R-0.40 b = 2 => T ~ R-0.33 kn ~ nb

  15. T Tauri Disks - Masses parameters k0 and b require knowledge of grain chemical composition shape size size distribution ... but b a good diagnostic?Larsson et al. 2000, 2002 White et al. 2000

  16. T Tauri Disks - Masses Opacitiesk(n) Beckwith et al. 2000 Gas-to-dust 100?

  17. T Tauri Disks - Structure Lynden-Bell & Pringle 1974

  18. T Tauri Disks - Structure 40 SEDs D´Alessio et al. 1999

  19. T Tauri Disks - Structure Steady Disks around Single Stars VW Cha: tidally truncated disk: 60 AU ESO-AO Brandeker et al. 2001

  20. T Tauri Disks - Structure Steady Disks around Single Stars Boundary Conditions in : boundary layer, magnetosphere out: ?, interstellar turbulence? Viscosity MHD/rotation Hawley & Balbus 1995 Opacity k = k(r, T,...) Models: Adams & Shu 1986 (flat) Kenyon & Hartmann 1987 (flared) Malbet & Bertout 1991 (vertical structure) D´Allessio et al. 1998,... 2001 Aikawa & Herbst 1998 (chemistry) Nomura 2002 (2D)

  21. T Tauri Disks - Make up 13CO (1) HCO+ (5) HCN (5) CO (200) HCO+ (200) HCN (200) T Tauri disks consist of gas and dust what components? in what proportions? van Zadelhoff 2002 LkCa 15 TW Hya

  22. T Tauri Disks - Chemistry Molecular abundances (rel. H2) Species LkCa 15 TW Hya CO 3.4(-7) 5.7(-8) HCO+ 5.6(-12) 2.2(-11) H13CO+ <2.6(-12) 3.6(-13) DCO+ …. 7.8(-13) CN 2.4(-10) 1.2(-10) HCN 3.1(-11) 1.6(-11) H13CN …. <8.4(-13) HNC …. <2.6(-12) DCN …. <7.1(-14) CS 8.5(-11) …. H2CO 4.1(-11) <7.1(-13) CH3OH <3.7(-10) <1.9(-11) N2H+ <2.3(-11) <1.8(-11) H2D+<1.5(-11) <7.8(-12) Thi 2002

  23. T Tauri Disks - Evolution Time scales (viscous accretion disk) tdyn ~ a ttherm ~ a (H/R)2 tvisc tdyn ~ 1/WKepler and a~ 10-3 - 10-2

  24. T Tauri Disks - Evolution Disk dispersal and disk lifetimes Hollenbach et al. 2000 Mass accretion evolution Calvet et al. 2000

  25. T Tauri Disks to Debris Disks fd = DLIR/Lvs stellar age Spangler et al. 2001

  26. Debris Disks - Images P. Kalas

  27. Debris Disks - Properties debris (collision products) or particulate (gas free) percentage of Main Sequence stars (?) (observationally) biased towards Spectral Type A for (detectable) ages <400 Myr Habing et al. 1999, 2001 disk sizes 100 to 1000 AU disk masses >1 to 100 MMoon (small dust) Pre-IRAS Solar system Zodi US Navy Chaplain G. Jones 1855 AJ 4, 94 Vega Blackwell et al. 1983

  28. THE Debris Disk – b Pictoris Sp. Type A5 V Hipparcos Input Catalogue 1992 Distance 19.3(0.2)pcHipparcos Catalogue 1997 Age 15(5) Myr Song et al. 2001 Metallicity solar Holweger & Rentzsch-Holm 1995 Disk size 1835 AU NE 1450 AU SW Larwood & Kalas 2001 Disk Mass dust: >0.44 MEarthChini et al. 1991 gas: see below

  29. b Pic Disk Model: Gas Best fit model (self consistent photoionisation calculation) to EMMI data with observed emission line flux Na D2 1.5 10-13 erg s-1 cm-2 line rel. flux (line/Na D) [C I] 370mm 3 10-7 [C I] 609mm 2 10-7 [C II] 157mm 1 10-2 dominates the cooling [O I] 63mm 2 10-3 [Si II] 35mm 1 10-3 [Fe II] 26mm 6 10-5 cf also Kamp & van Zadelhoff 2001, van Zadelhoff 2002

  30. b Pictoris obser-vation model model New: gas disk extension to >300 AU in e.g. Na I D2 Olofsson et al. 2001 VLT 2002 =>

  31. THE Debris Disk – b Pictoris Presence of substantial amounts of H2 debated Thi 2002 Presence of atomic gas – no doubt Olofsson et al. 2001 new VLT data reveal disk flaring in e.g. CaII HK and... slit height 8´´

  32. THE Debris Disk – b Pictoris The VLT Disk Spectrum (340 – 390 nm) only permitted lines no Fe II, no H I Fe I multiplets 4, 5, 40, 41 Ca II H & K Tbc Ni I, Ti I, V II, Cr I, Co I, Mn I, Ru I, Ce II, Tm I

  33. THE Debris Disk – b Pictoris 1200 mm (SEST) ...and the ``Blob´´ 850 mm (JCMT)

  34. THE Debris Disk – b Pictoris SCUBA JCMT 850mm SIMBA SEST 1200mm Holland et al. 1998 Peak position +0.8, +9.7 arcsec 0, 0 Peak flux 58.3(6.5) mJy/beam 48.8(1.2) mJy/beam Deconvolved size 22´´ x 11´´ 26´´ x 10´´ Blob position -21, -26 arcsec -26, -44 arcsec Position angle 39.6 deg 31.5 deg Distance 34´´ 52´´ Flux 19.1(6.5) mJy/beam 19.7(4.2) mJy/beam Ratio 3.0(1.1) 2.5(0.5)

  35. THE Debris Disk – b Pictoris Blob real? If so, associated with b Pic? Assume opacity exponents a for Blob and b for b Pic R1200/R850 = (850/1200)b-a b - a = 0.53 (+0.38, -0.68) if b = 0.8 (Wyatt & Dent 2002) then a = 0.3 a ~ b? a = [-0.11, 0.65]

  36. Debris Disks and Planets Disks have non-homogeneous structure – not simple power law distributions because of planet(s)? b Pic Keck 18 mm Wahhej et al. 2002 Heap et al. 2000

  37. Debris Disks and Planets Disks have non-homogeneous structure – not simple power law distributions because of planet(s)? a Lyr 1.3 mm (PdB) Model: excentric ``Jupiter´´ Wilner et al. 2002

  38. Debris Disks and Planets Do ``Planet-Stars´´ have disks? 55 Cnc No! Jayawardhana et al. 2002 r CrB tbc Trilling et al. 2000 HD 210277 tbc e Eri a border case? Hatzes et al. 2000

  39. Disks: Open Questions Grain growth: from micron to cm size from cm to 100 m+ size Time of (giant) planet formation termination of planet migration Processes/time scales of disk dispersal formation and evolution of debris disks Role of stellar multiplicity free-floating planets

  40. Disks and GENIE Angular resolution of order 2.5 (lmm)/b100m mas Debris disks generally at l > 25 mmLaureijs et al. 2002 L-band (1000 K), N-band (300 K) L-band: min(kscat, kabs) T Tauri disk: 0.4 AU 3 mas Debris disk: 1.2 AU 60 mas N-band: hot telescope/sky T Tauri disk: 9 AU 60 mas Debris disk: 25 AU 1.2 arcsec

  41. Debris Disks and Planets e Eri Vega

  42. b Pic Disk Models Best fit model (self consistent photoionisation calculation) to EMMI data with observed emission line flux Na D2 1.5 10-13 erg s-1 cm-2 line relative flux [C I] 370mm 3 10-7 [C I] 609mm 2 10-7 [C II] 157mm 1 10-2 [O I] 63mm 2 10-3 [Si II] 35mm 1 10-3 [Fe II] 26mm 6 10-5 cf also Kamp & van Zadelhoff 2001, van Zadelhoff 2002

  43. b Pic: Atomic Gas Mass N(Na) = 61010 cm-2 if Na/H solar (210-6), then N(HI) = 31016 cm-2 * *cf. Freudling et al. 1995, AA 301, 231: N(HI)  1019 cm-2 Disk Absorption Line: @systemic/stellar velocity EW(NaD2) = 9.4 mÅ*  M(Na) 21017 g [M(dust) 21027 g] *cf. Vidal-Madjar et al. 1986, AA 167, 325 Disk Emission Line: EW(NaD2) = 0.72 mÅ  (disk) = 8.8 deg [r0(NaD) = 30 AU, H0(disk) = 4.6 AU]* *cf. Z(x) = 0.055 rmax x0.75 , x = r/ rmax rmax =120 AU

More Related