L6 - Stellar Evolution I: November-December, L 6: Circumstellar Disks Background image: HH 30 JHK HST-NICMOS, courtesy Padgett et al. 1999, AJ 117, 1490

L6 - Stellar Evolution I: November-December, L 6: Circumstellar Disks Background image: HH 30 JHK HST-NICMOS, courtesy Padgett et al. 1999, AJ 117, 1490 The Formation of Stars Chapters: 11, 13

L6 - Stellar Evolution I: November-December, L 6: Circumstellar Disks Recent reviews include: Protostars & Planets IV, Mannings, Boss & Russell (eds.) 12 Articles on Disks 5 Articles on Outflows Zuckerman, ARAA 2001, 39: 549 Zuckerman & Song, ARAA 2004, 42: 685 Protostars & Planets V (2005)

L6 - Stellar Evolution I: November-December, L 6: Circumstellar Disks and Outflows

L6 - Stellar Evolution I: November-December, Flattened structures - Disks Inevitable consequence of star formation Rotation Magnetic Fields Rotation

L6 - Stellar Evolution I: November-December, Flattened structures - Disks Inevitable consequence of star formation Rotation P.S. Laplace 1796, 1799 Exposition du systeme du monde Mechanique celeste I. Kant 1755 Allgemeine Naturgeschichte und Theorie des Himmels Planetary System Formation Astrobiology School: Q

L6 - Stellar Evolution I: November-December, Mass Loss - Outflows Inevitable consequence of star formation Angular Momentum Loss - Redistribution The race between mass accretion & mass loss processses

L6 - Stellar Evolution I: November-December, Lynden-Bell & Pringle 1974, MNRAS 168, 603: Keplerian Disk Differential Rotation + Viscosity Mass Transport Inwards Angular Momentum Transport Outwards

L6 - Stellar Evolution I: November-December, `standard model´: e.g., Frank, King & Raine Accretion Power in Astrophysics self-consistent structure of steady, optically thick  -disk blackbody radiation and thin disk approximation When / Where valid ?

L6 - Stellar Evolution I: November-December, Example: Lin & Papaloizou opacities (1985 PP II): Icy grains H - Molecules bound-free free-free (Cox-Stuart-Alexander)

L6 - Stellar Evolution I: November-December, Beckwith et al. 2000, PP IV Grain Opacities See Ph. Thebault’s lecture

L6 - Stellar Evolution I: November-December, `standard model´: e.g., Frank, King & Raine Accretion Power in Astrophysics self-consistent structure of steady, optically thick a-disk

L6 - Stellar Evolution I: November-December, observed SEDs of T Tauri Stars & `mean model´ of star+disk D´Alessio et al HABE Disk Structure: Dullemond & Dominik 2004 includes vertical Temperature distribution

L6 - Stellar Evolution I: November-December, Gas Disks – Structure Models Steady Disks around Single Stars Boundary Conditions R in : boundary layer, magnetosphere, hole? R out : ad hoc?, interstellar turbulence? Viscosity MHD/rotation (Hawley & Balbus 1995) Opacity , T, …, XYZ,...,  , ...,  ...) ModelsAdams & Shu 1986 (flat) [examples] Kenyon & Hartmann 1987 (flared) Malbet & Bertout 1991 (vertical structure) D´Allessio et al. 1998, Aikawa & Herbst 1998 (chemistry) Nomura 2002 (2D) Wolf 2003 (3D) See G. Mellema’s lecture

L6 - Stellar Evolution I: November-December, Observations of Keplerian Disks JE Keeler 1895 ApJ 1: 416 The Rings of Saturn spectrum image Courtesy Brandeker, Liseau & Ilyn 2002

L6 - Stellar Evolution I: November-December, Categories of Disks observed T Tauri Disks: around young stars ( Myr) of half a solar mass ( M sun ) at 150 pc distance ( pc) in and/or near molecular clouds Accretion Disks Debris Disks: around young ms-stars ( Myr) of about a solar mass (1 - 2 M sun ) at 20 pc distance ( pc) in the general field Vega-excess stellar disks gas rich gas poor

L6 - Stellar Evolution I: November-December, Frequency of Disks High Rate of occurence around young stars NGC % Trapezium cluster 80% IC % Haisch et al and around BDs in Trapezium cluster 65% Muench et al see also G. Gahm’s lecture

L6 - Stellar Evolution I: November-December, Gas Disks - Sizes Size scale (AU)Tracer (mode)*Reference 20000CS (1- 0) (S)Kaifu et al CO (1- 0) (S)Fridlund et al C 18 O (1- 0) (I)Sargent et al < mm (I)Woody et al mm, cm (I)Keene & Masson mm (I)Lay et al H 13 CO + (1- 0) (S)Mizuno et al mm (S)Ladd et al C 18, 17 O (2- 1) (S)Fuller et al CO (1- 0) (I)Ohashi et al H 13 CO + (1- 0) (I)Saito et al H 12, 13 CO + (1- 0) (S, I)Hogerheijde et al.1997, C 18 O + (1- 0) (I)Momose et al mm (I)Rodriguez et al CH 3 OH (2-1), (5-4) (S)White et al Fridlund et al for One Object: L1551 Size depends on frequency/mode of observation * S=single dish, I=Interferometer

L6 - Stellar Evolution I: November-December, Gas Disks - Sizes T Tauri/HABE disks AUDust: mm-continuum interferometry AUDust: scattered stellar light 300 AUGas: CO lines (evidence for Kepler rotation) Silhouettte disks (``proplyds´´) up to 1000 AUDust: scattered stellar light generally

L6 - Stellar Evolution I: November-December, Gas Disks - Masses H 2 Gas Directly CO and Dust blueshifted CO redshifted CO continuum

L6 - Stellar Evolution I: November-December, Gas Disks - Masses Lower limit: to 1 M Sun (based on mm / submm continuum) How good are these numbers ? Do we understand disks ? ? Why ? dust gas +dust Solar Minimum Mass Nebula = M Sun

L6 - Stellar Evolution I: November-December, Gas Disks - Make up gas disks consist of gas and dust what components? what proportions?

L6 - Stellar Evolution I: November-December, T Tauri Disks - Make up van Zadelhoff CO (1)* HCO + (5) HCN (5) CO (200) HCO + (200) HCN (200 ) LkCa 15TW Hya * (N) = depletion factor

L6 - Stellar Evolution I: November-December, T Tauri Disks - Chemistry Molecular abundances (rel. H 2 ) Species LkCa 15TW Hya CO3.4 ( - 7)5.7 ( - 8) HCO (-12)2.2 (-11) H 13 CO + < 2.6(-12)3.6 (-13) DCO + ….7.8 (-13) CN2.4 (-10)1.2 (-10) HCN3.1 (-11)1.6 (-11) H 13 CN….< 8.4(-13) HNC….< 2.6(-12) DCN….< 7.1(-14) CS8.5 (-11)…. H 2 CO4.1 (-11)< 7.1(-13) CH 3 OH< 3.7(-10)< 1.9(-11) N 2 H + < 2.3(-11)< 1.8(-11) H 2 D + < 1.5(-11)< 7.8(-12) Thi 2002

L6 - Stellar Evolution I: November-December, Gas Disks - Evolution Time scales (viscous accretion disk) t dyn ~  t therm ~  (H/R) 2 t visc t dyn ~ 1/  Kepler  ~ H/R << 1 if T ~ R -1/2, t visc ~ R t visc ~ 10 5 yr (  /0.01) -1 (R/10 AU)

L6 - Stellar Evolution I: November-December, Gas Disks - Evolution Disk dispersal and disk lifetimes Physical Mechanisms Hollenbach et al PPIV SE = Stellar Encounter (tidal stripping) WS = Stellar wind stripping evap E = photoevaporation external star evap c = photoevaporation central star All for Trapezium conditions T ~ R -0.5, t visc ~ R t visc ~ 10 5 yr (  /0.01) -1 (R/10 AU)

L6 - Stellar Evolution I: November-December, Gas (T Tauri) Disks - Evolution Disk dispersal and disk lifetimes Mass accretion evolution Calvet et al PPIV Average Error Bar

L6 - Stellar Evolution I: November-December, Gas Disks to Debris Disks – Evolution ? See also lecture by Ph. Thebault f dust =  L IR /L vs stellar age (F)IR - excess Stellar luminosity (bolometric) How ?

L6 - Stellar Evolution I: November-December, Gas Disks to Debris Disks – Evolution ? Spangler et al Clusters Individual stars (= 1 zodi)

L6 - Stellar Evolution I: November-December, HR 4796A  Pic HD Rieke et al. 2005, ApJ 620,  m Spitzer data 266 ms stars

L6 - Stellar Evolution I: November-December, Debris Disks - Properties debris (collision products) or particulate (gas free) percentage of Main Sequence stars (15%?) (observationally) biased towards Spectral Type A for (detectable) ages <400 Myr Habing et al. 1999, 2001 disk sizes 100 to 2000 AU disk masses >1 to 100 M Moon (small grains) see Ph. Thebault’s lecture Pre-IRAS Solar system Zodi US Navy Chaplain G. Jones 1855 AJ 4, 94 Vega Blackwell et al. 1983

L6 - Stellar Evolution I: November-December,

L6 - Stellar Evolution I: November-December, How much Gas in Dusty Debris Disks ? Disk evolution hypothesis: gas-rich to gas-poor Census of material (m gas /m dust ): planet formation planet formation: enough gas for GPs ? planet formation: time scales ? planet formation: seeds of Life ? See astrobiology lecture

L6 - Stellar Evolution I: November-December, Putting it all together Outflows Infall Disks L 1551 IRS 5 - a protostellar binary

L6 - Stellar Evolution I: November-December, L 1551 IRS 5 Jet blue 10´´ Molecular Outflow – CO blue 2 arcmin Optical Image (NTT, R-band)

L6 - Stellar Evolution I: November-December, Jets !!! – HST-R + spectroscopy Fridlund & Liseau 1998, ApJ 499, L75 N: Bright and Fast S: Faint and Slow

L6 - Stellar Evolution I: November-December, Also 2 Radio Jets – 3.5 cm VLA (arcsec) Rodriguez et al. 2003, ApJ 586, L137 Counter jet(s)

L6 - Stellar Evolution I: November-December, Proper Motion of Disk Sources - VLA 2cm Rodriguez et al. 2003, ApJ 583, 330

L6 - Stellar Evolution I: November-December, Stahler et al. - Stahler - Palla & Stahler 1980 through 1993 F. Palla, priv. communication Mass-Radius relation (M/R)

L6 - Stellar Evolution I: November-December, Putting it all together: observation + theory of infall + theory of mass loss L 1551 IRS 5 - a protostellar binary

L6 - Stellar Evolution I: November-December, Putting it all together: observation + theory of infall + theory of mass loss L 1551 IRS 5 - a protostellar binary

L6 - Stellar Evolution I: November-December, adapted from Liseau, Fridlund & Larsson 2005, ApJ, 619, 959 MHD x-wind models: ang. momentum parameter J

L6 - Stellar Evolution I: November-December,

L6 - Stellar Evolution I: November-December, Stellar Atmosphere Models Observed Spectrum (upper curves) Combined Rotating Model (lower )

L6 - Stellar Evolution I: November-December, After collaps and /or main accretion phase: Pre-main-sequence evolution begins next lecture by G. Gahm

L6 - Stellar Evolution I: November-December, L 6: conclusions circumstellar disks are a consequence of star formation disks and bipolar outflows/jets are connected disks form potentially planetray systems L 6: open questions what are the physics of disks and their outflows ? how do disks evolve ? what fraction forms planetary systems ? when and how ?