protoplanetary transition disks

Transcription

1 protoplanetary transition disks (Harvard-CfA) 1. disk evolution and planets why does disk dispersal matter? 40 AU orbit 2. transition disks definitions and observational signatures SMA 880 microns 3. resolved structures direct-imaging of large disk cavities [Andrews et al., in prep] 4. potential origins tidal interactions, links to orbital evolution also: David Wilner, Charlie Qi, Catherine Espaillat (CfA), Meredith Hughes (Berkeley), and others... [NASA/JPL/T. Pyle (SSC)] 1/10

2 the evolution of disk structure: slow, then fast timeline (to scale!) ~0.5 Myr (?) formation < 5-10 Myr viscous evolution (+particle growth) ~ few x 0.1 Myr dissipation how much time is available for planet formation? 1/2-life ~3 Myr disk signatures vs. time: hot dust gone by ~10 Myr accretion signatures also only material inside 1 AU [compiled by Mamajek 2009] 2/10

3 the evolution of disk structure: slow, then fast timeline (to scale!) ~0.5 Myr (?) formation < 5-10 Myr viscous evolution (+particle growth) ~ few x 0.1 Myr dissipation how much time is available for planet formation? 1/2-life ~3 Myr disk signatures vs. time: hot dust gone by ~10 Myr accretion signatures also only material inside 1 AU but the answer depends on the signature small subset of disks are evolving from the inside out [compiled by Mamajek 2009] 2/10

4 the transition disks (and what that means) These objects represent...disks whose inner regions are relatively devoid of distributed matter, although the outer regions still contain substantial amounts of dust. [Strom et al. 1989] [e.g., Furlan et al. 2009] 3/10

5 the transition disks (and what that means) These objects represent...disks whose inner regions are relatively devoid of distributed matter, although the outer regions still contain substantial amounts of dust. [Strom et al. 1989] [e.g., Furlan et al. 2009] what I mean: a disk with a large reduction in optical depth near the star (i.e., a cavity or hole ) 3/10

6 the transition disks (and what that means) These objects represent...disks whose inner regions are relatively devoid of distributed matter, although the outer regions still contain substantial amounts of dust. [Strom et al. 1989] [e.g., Furlan et al. 2009] what I mean: a disk with a large reduction in optical depth near the star (i.e., a cavity or hole ) 3/10

7 the transition disks (and what that means) missing warm dust near the star These objects represent...disks whose inner regions are relatively devoid of distributed matter, although the outer regions still contain substantial amounts of dust. [Strom et al. 1989] [e.g., Furlan et al. 2009] what I mean: a disk with a large reduction in optical depth near the star (i.e., a cavity or hole ) 3/10

8 the transition disks (and what that means) missing warm dust near the star These objects represent...disks whose inner regions are relatively devoid of distributed matter, although the outer regions still contain substantial amounts of dust. [Strom et al. 1989] [e.g., Furlan et al. 2009] what I mean: a disk with a large reduction in optical depth near the star (i.e., a cavity or hole ) model density map synthetic sub-mm image 3/10

9 the transition disks (and what that means) missing warm dust near the star These objects represent...disks whose inner regions are relatively devoid of distributed matter, although the outer regions still contain substantial amounts of dust. [Strom et al. 1989] [e.g., Furlan et al. 2009] what I mean: a disk with a large reduction in optical depth near the star (i.e., a cavity or hole ) model density map synthetic sub-mm image they seem to be rare: ~1% (1 Myr); ~10% (3 Myr) [Muzerolle et al. 2010] 3/10

10 resolved transition disk structures with the SMA new results from an SMA census of the nearest transition disks 0.85 mm, 0.3 ~20 AU resolution 2-D Monte Carlo RT (RADMC) modeling of SED+SMA data as in Andrews et al. 2009, /10

11 resolved transition disk structures with the SMA new results from an SMA census of the nearest transition disks 0.85 mm, 0.3 ~20 AU resolution 2-D Monte Carlo RT (RADMC) modeling of SED+SMA data as in Andrews et al. 2009, /10

12 resolved transition disk structures with the SMA new results from an SMA census of the nearest transition disks 0.85 mm, 0.3 ~20 AU resolution 2-D Monte Carlo RT (RADMC) modeling of SED+SMA data as in Andrews et al. 2009, 2010 a very simple structure model successfully reproduces the data 4/10

13 resolved transition disk structures with the SMA new results from an SMA census of the nearest transition disks 0.85 mm, 0.3 ~20 AU resolution 2-D Monte Carlo RT (RADMC) modeling of SED+SMA data as in Andrews et al. 2009, 2010 a very simple structure model successfully reproduces the data SpT A5-M4 (M ~ M ) ages from <1-3 Myr 4/10

14 resolved transition disk structures with the SMA new results from an SMA census of the nearest transition disks 0.85 mm, 0.3 ~20 AU resolution 2-D Monte Carlo RT (RADMC) modeling of SED+SMA data as in Andrews et al. 2009, 2010 a very simple structure model successfully reproduces the data SpT A5-M4 (M ~ M ) ages from <1-3 Myr 4/10

15 resolved transition disk structures with the SMA new results from an SMA census of the nearest transition disks 0.85 mm, 0.3 ~20 AU resolution 2-D Monte Carlo RT (RADMC) modeling of SED+SMA data as in Andrews et al. 2009, 2010 a very simple structure model successfully reproduces the data SpT A5-M4 (M ~ M ) ages from <1-3 Myr 4/10

16 resolved transition disk structures with the SMA new results from an SMA census of the nearest transition disks 0.85 mm, 0.3 ~20 AU resolution 2-D Monte Carlo RT (RADMC) modeling of SED+SMA data as in Andrews et al. 2009, 2010 a very simple structure model successfully reproduces the data SpT A5-M4 (M ~ M ) ages from <1-3 Myr 4/10

17 resolved transition disk structures with the SMA new results from an SMA census of the nearest transition disks 0.85 mm, 0.3 ~20 AU resolution 2-D Monte Carlo RT (RADMC) modeling of SED+SMA data as in Andrews et al. 2009, 2010 a very simple structure model successfully reproduces the data SpT A5-M4 (M ~ M ) ages from <1-3 Myr 4/10

18 new insights on transition disk structures new model surface density fits, compared with MMSN giant planets no resolved info for R<15-20 AU transition disk cavities are: very large: Rcav ~ AU very empty: δσ ~ x (?) but, their outer disks are similar to normal disks (a bit denser on average) in general, they still accrete! (be wary: a little dust in the cavity goes a long way) 5/10

19 some proposed alternative origins for the cavities photoevaporation ionizing photons wind (remove material) in these cases, doesn t work: cavities too large accretion rates too high X-ray luminosities too low grain growth normal dust (change emissivity) this might work: need very large solids (m+) change solids in narrow zone maybe trouble with gas? 6/10

20 some proposed alternative origins for the cavities photoevaporation ionizing photons wind (remove material) in these cases, doesn t work: cavities too large accretion rates too high X-ray luminosities too low grain growth normal dust (change emissivity) this might work: need very large solids (m+) change solids in narrow zone maybe trouble with gas? 6/10

21 some proposed alternative origins for the cavities photoevaporation ionizing photons wind (remove material) in these cases, doesn t work: cavities too large accretion rates too high X-ray luminosities too low grain growth normal dust (change emissivity) this might work: need very large solids (m+) change solids in narrow zone maybe trouble with gas? 6/10

22 some proposed alternative origins for the cavities photoevaporation ionizing photons wind (remove material) in these cases, doesn t work: cavities too large accretion rates too high X-ray luminosities too low grain growth normal dust (change emissivity) this might work: need very large solids (m+) change solids in narrow zone maybe trouble with gas? 6/10

23 some proposed alternative origins for the cavities photoevaporation ionizing photons wind (remove material) in these cases, doesn t work: cavities too large accretion rates too high X-ray luminosities too low grain growth normal dust (change emissivity) this might work: need very large solids (m+) change solids in narrow zone maybe trouble with gas? 6/10

24 some proposed alternative origins for the cavities photoevaporation ionizing photons wind (remove material) in these cases, doesn t work: cavities too large accretion rates too high X-ray luminosities too low grain growth normal dust (change emissivity) this might work: need very large solids (m+) change solids in narrow zone maybe trouble with gas? 6/10

25 some proposed alternative origins for the cavities photoevaporation ionizing photons wind (remove material) in these cases, doesn t work: cavities too large accretion rates too high X-ray luminosities too low grain growth normal dust (change emissivity) this might work: need very large solids (m+) change solids in narrow zone maybe trouble with gas? 6/10

26 some proposed alternative origins for the cavities photoevaporation ionizing photons wind (remove material) in these cases, doesn t work: cavities too large accretion rates too high X-ray luminosities too low grain growth normal dust (change emissivity) this might work: need very large solids (m+) change solids in narrow zone maybe trouble with gas? 6/10

27 some proposed alternative origins for the cavities photoevaporation ionizing photons wind (remove material) in these cases, doesn t work: cavities too large accretion rates too high X-ray luminosities too low grain growth large solids normal dust (change emissivity) this might work: need very large solids (m+) change solids in narrow zone maybe trouble with gas? 6/10

28 disk-companion (planet?) tidal interactions companion(s) 7/10

29 disk-companion (planet?) tidal interactions companion(s) companion 7/10

30 disk-companion (planet?) tidal interactions companion(s) companion giant planet cores (ice giants) gap only; low impact on M flow 7/10

31 disk-companion (planet?) tidal interactions companion(s) companion giant planet cores (ice giants) gap only; low impact on M flow 7/10

32 disk-companion (planet?) tidal interactions companion(s) companion giant planet cores (ice giants) gap only; low impact on M flow giant planets (Jupiters). low-density cavity; M~1-10% 7/10

33 disk-companion (planet?) tidal interactions companion(s) companion giant planet cores (ice giants) gap only; low impact on M flow giant planets (Jupiters). low-density cavity; M~1-10% 7/10

34 disk-companion (planet?) tidal interactions companion(s) companion giant planet cores (ice giants) gap only; low impact on M flow giant planets (Jupiters). low-density cavity; M~1-10% 7/10

35 disk-companion (planet?) tidal interactions companion(s) companion giant planet cores (ice giants) gap only; low impact on M flow giant planets (Jupiters). low-density cavity; M~1-10% 7/10

36 disk-companion (planet?) tidal interactions companion(s) companion giant planet cores (ice giants) gap only; low impact on M flow giant planets (Jupiters). low-density cavity; M~1-10% [Phil Armitage] 7/10

37 disk-companion (planet?) tidal interactions companion(s) companion giant planet cores (ice giants) gap only; low impact on M flow giant planets (Jupiters). low-density cavity; M~1-10% stars/brown dwarfs. very empty cavity; M < 1% [Phil Armitage] 7/10

38 disk-companion (planet?) tidal interactions companion(s) companion giant planet cores (ice giants) gap only; low impact on M flow giant planets (Jupiters). low-density cavity; M~1-10% stars/brown dwarfs. very empty cavity; M < 1% [Phil Armitage] 7/10

39 the transition disks (and why you should care) these cavities might be the telltale signatures of extremely young (~1 Myr) giant exoplanets if so, they are our best bet for studying disk-planet interactions... accretion in the feeding zone migration, disk dissipation and may be a novel way of indirectly finding long-period exoplanets cavity size ~ semimajor axis mass in cavity ~ mass of planet [Rice et al. 2008] such interactions are among the most important factors that shape exoplanet properties (orbits, masses, composition, etc) 8/10

40 (near) future: transition disks and exoplanet searches disk + planet (density) ALMA simulation [Wolf & D Angelo 2006] 9/10

41 (near) future: transition disks and exoplanet searches disk + planet (density) ALMA simulation real SMA data (different resolution) [Wolf & D Angelo 2006] [Andrews et al. 2009] 9/10

42 (near) future: transition disks and exoplanet searches disk + planet (density) ALMA simulation real SMA data (different resolution) [Wolf & D Angelo 2006] [Andrews et al. 2009] new tool for exoplanet searches: high resolution radio imaging indirect search method (then high resolution IR followup) young (1 Myr), massive (>1 MJup), long-period (>5 AU) major advances in sensitivity/resolution with ALMA 9/10

43 are transition disks the precursors of debris belts? directly imaged planets inside debris belts transition disk LkCa 15 [Lagrange et al. 2008]? debris disk Formalhaut [Kalas et al. 2008] [Wilner, Andrews, & Hughes 2010] 10/10