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Disks, Massive Stars, Proplyds, Planets John Bally

Disks, Massive Stars, Proplyds, Planets John Bally. Stars: The fundamental building blocks of the Universe: Massive stars: ~8 to > 100 x mass of Sun Lumnious: 10 3 to 10 7 x Sun Short-lived: 3 to 30 million years Rare Moderate mass stars: 2 to 8 x mass of Sun

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Disks, Massive Stars, Proplyds, Planets John Bally

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  1. Disks, Massive Stars, Proplyds, Planets John Bally

  2. Stars: The fundamental building blocks of the Universe: Massive stars: ~8 to > 100 x mass of Sun Lumnious: 103 to 107 x Sun Short-lived: 3 to 30 million years Rare Moderate mass stars: 2 to 8 x mass of Sun Bright: 10 to 103 x Sun Lifetime: 30 million to ~ 1 billion years Common Low-mass stars: 0.08 to 1 x mass of Sun Dim: 10 to 10-3 x Sun Long-lived: 1 to > 300 billion years ! Very common: 90 % of stars Brown dwarves to planets: < 0.08 x mass of Sun No nuclear fusion, cool, faint

  3. Star Formation Shrink size by 107; increase density by x 1021 ! Where planets also form • Giant Molecular Cloud Core Raw material for star birth • Gravitational Collapse & Fragmentation Proto-stars, proto-binaries, proto-clusters • Rotation & Magnetic Fields Accretion disks, jets, & outflows • Planets Most may form in clusters! C. Lada

  4. Accretion disk:

  5. Collapse of a 10 Mo, rotating cloud t = 65,000 yr: M* = 7 Mo, Mdisk = 2.8 Mo, Menv = 0.2Mo

  6. Taurus disks & jets: Karl Stapelfeldt et al.

  7. Star + Disk magnetospheres

  8. Star + Disk magnetospheres

  9. “Funnel Flows” (A. Konigl)

  10. 2.12 m H2 (blue) 11.7 m (orange) Smith et al. (2005) + Cunningham (2008)

  11. OMC1 H2 fingers Kaifu et al. (00); Underhill et al. (01)

  12. HH 212 H2 (Mc Caughrean & Zinnecker VLT)

  13. Outflows: Jets, Winds => Wide-Angle Cavities Internal working surfaces Terminal working surface Disk winds X-winds HH jet (high V) HI H2 (moderate V) CO outflow (low V)

  14. L1551 (BR06) HH 30 (HST) X-ray source ~0.5” from IRS5 Ha [SII] CO J=2-1

  15. L1551 CO J=2-1 6-7 km/s 8-12 km/s 1-5 km/s

  16. Flow Properties Parameter (M<5 Solar) (M>5 Solar) unit • Wind/jet velocity 100 - 1,000 100 - 1,000 km/s • dM/dt 10-5 to 10-9 10-5 to 10-2Mo yr-1 • M(H2) 0.001 to 10 1 to 3,000 Mo • t 104 (Class 0) 104 to 105yr • 105 (Class I) yr • 106 (>Class II) yr • Size: 1 to 10 1 to 20 pc • E 1043 to 1047 1046 to 1050erg • Lmech 10-0 to 10-3 10-1 to 103 Lo

  17. Jets from Young Stars • Fossil Record of Accretion &Mass-loss: • Tracer of stellar birth over 105 years • Feedback / Self-Regulation of Star formation: • Lowest rung of “feedback ladder” • Laboratory for ALL collimated outflow phenomena: • Planetary nebulae, Symbiotic systems (WDs, NSs) • QSOs, AGN, ….. • Accretion + Rotation + Magnetic Fields => JETS

  18. Jet Acceleration & Collimation • dM /dt increases as L0.8 • V increases as L0.2 • Acceleration Mechanisms: • - Radiation pressure ? NO - L/c too low • - Thermal pressure gradient? NO • - MHD YES! • Uchida-Shibata, Lovelace – helical torsion, impulsive • Pudritz-Norman disk wind - advected B, steady • Shu X-wind - stellar dynamo, steady • - Dynamical decay; release of gravitational potential (Orion) • Collimation: • - Magnetic hoop stress • - Ambient density gradient • - Ram-pressure of infalling • envelope

  19. Bate, M. R., Bonnell, I. A., Bromm, V., 2002, MNRAS, 332, L65-L68 SPH: No radiation No B No outflows.

  20. The “ecology” of Star and Planet Formation Orion Nebula: 2,000 Mo NGC 3603: 30,000 Mo 30 Doradus (LMC): 500,000 Mo

  21. Luminosity, Radius, K-H time-scale vs. Mass

  22. O-star Mass vs. spectral & luminosity class

  23. Lyman continuum luminosity vs. Mass, time 120 Mo 85 60 40 25 20

  24. L/M, Laccretionand opacity vs. Mass

  25. H-R: Non-accreting vs. Accretiional growth

  26. Stellar Death:

  27. OH 231.8+4.2 “Rotten Egg”, Callibash, …

  28. Planet Formation

  29. UV photo-ablation of disks & planet formation: Smith, Bally, Licht, Walawender 05 d253-535 in M43

  30. How common are close approaches? 1” = 500 AU HST 16 200 AU diameter HST 10 0.3 ly to O star HST 17 Bally et al. 98

  31. Growing grains:Si 10 m feature(Shuping et al. 2006)

  32. d181-825 “Beehive” proplydChandra COUP Jet Star Photo-ablation flow metal depleted! (Kastner et al. 2005, ApJS, 160, 511) 8; 10 20 cm 1200 AU

  33. 6 – 13.6 eV UV photons

  34. 6 – 13.6 eV UV photons

  35. 6 – 13.6 eV UV photons

  36. 6 – 13.6 eV UV photons

  37. > 13.6 eV photons 6 – 13.6 eV UV photons

  38. > 13.6 eV photons 6 – 13.6 eV UV photons

  39. Stellar wind > 13.6 eV photons 6 – 13.6 eV UV photons

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