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S106 star forming region in Cygnus (Subaru telescope)

Overview of Disks & Associated Phenomena . John Bally. S106 star forming region in Cygnus (Subaru telescope). S106 star forming region in Cygnus (Subaru telescope). Outline Disks are ubiquitous - Angular momentum + dissipation => Disks galaxies, AGN, young stars, post-AGB, PN

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S106 star forming region in Cygnus (Subaru telescope)

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  1. Overview of Disks & Associated Phenomena John Bally S106 star forming region in Cygnus (Subaru telescope)

  2. S106 star forming region in Cygnus (Subaru telescope)

  3. Outline • Disks are ubiquitous • - Angular momentum + dissipation => Disks • galaxies, AGN, young stars, post-AGB, PN • supernovae, neutron stars, black-holes, • symbiotic systems, proto-planets, … • Disks in star formation • - Angular momentum transport • - Magnetic field dissipation • - Jet / outflow production • - Massive Star Formation • - Planet formation • Hazards to planet formation: • - UV radiation • - Stellar dynamics Planets form fast or will be rare (< 5% of stars)

  4. Star Formation Where planets also form • Giant Molecular Clouds (GMCs) Raw material for star birth • Gravitational Collapse & Fragmentation Proto-stars, proto-binaries, proto-clusters • Rotation & Magnetic Fields Accretion disks, jets, & outflows

  5. Gravitational Condensation Giant Molecular Cloud Star Forming Cloud Core • Stars Form in Dense Groups, Clusters • Cores Disrupted After Converting 5 to 20% • of their Mass into Stars: Disruption by • Outflows, UV radiation (Massive Stars)

  6. Giant Molecular Cloud Star Forming Core Accretion Disks + Proto-Stars

  7. Gravity, Spin, Magnetic Fields Gravity Disks Rotating Core Jets

  8. Young Stars Form in Groups

  9. Disks, B, Stellar Rotation, & Jets

  10. Bate, Bonnell, Bromm (2002) U.K. Astrophysical Fluid Facility M = 50 Solar masses L = 1.2 l.y. T = 10 K

  11. The Orion Star Forming Complex

  12. Infrared view of winter sky (10 - 120 mm) IRAS

  13. Orion Molecular Clouds 13 Orion B 2.6 mm CO Orion Nebula Orion A

  14. Optical

  15. CO

  16. Orion A: Outflows churn cloud M42 HH34 HH 1/2

  17. HH 3 NGC 1999 New jet HH 1 Orion: 1 deg. S of Orion Nebula HH 2 proplyd

  18. HH 1/2

  19. HH 1/2

  20. HH 1 jet

  21. HH 1 jet

  22. HH 1

  23. HH 1

  24. HH 2

  25. HH 2

  26. HH 111 jet

  27. HH 111 jet

  28. HH 111 Ha + [SII] [Fe II] + K WFPC2 NICMOS

  29. Orion below the Belt: NGC 2024 (OB1 d) Horsehead Nebula s Orionis (OB 1 c) NGC 1977 (OB1c) Orion Nebula (OB1 d) i Ori (OB 1c)

  30. Orion Nebula 2MASS (near infrared) 2000 low & intermediate mass stars + 10 high mass stars Nearest massive star forming region

  31. OMC1 Core 2.12 mm H2 10 mm

  32. New Jet

  33. Protostellar cannibalism ? Near Infrared

  34. OMC1: SiO, H2

  35. OMC1 SiO masers

  36. Massive Star Formation Models: • Direct Accretion (< 15 to 30 Mo)? • Scaled-up version of low M star formation • - In isolated, ultra-dense cores • - Radiation pressure halts infall • - Accretion onto and through disk? • Cannibalism (> 15 to 30 Mo )? • Something new: protostellar coalescence • - In ultra-dense clusters • - Assisted by disks, envelopes e.g. Behrend & Maeder (2001) e.g. Bonnell et al (1998)

  37. Types of Cannibalism Core-Core Core-Disk Core-Star Disk-DiskDisk-Star Star-Star Low L, weak shocks, IR lines of H2 High L IR flares, non-thermal radio, X-ray Very rare, galactic nucleii, assisted by red supergiants

  38. Energetics of Cannibalism Energy released in merger: m = 1 Mo fG mM r + R E = ~ 8 x 1048 (erg)forM = 30 Mo r+R = 1012 cm Emin = 3 x 1046 ergsform = M = 0.1 Mo @ 1011 cm Emax = 3 x 1051 ergsform = M = 100Mo @ 1012 cm Release time-scale: Radiative time >> dynamical time t = 1 to 100 years Luminosity:L ~ E/t ~ 200 Lo to 2 x 1011 Lo ! IR flares: Rate ~ 1 to 10 x SN rate.

  39. Disk Assisted Merging: v(m) m rG1 rG r M • Gravitational focusing: • rG1 = (2 GM r)1/2 / v(m) ~ 0.7 Mo1/2 r111/2 v5-1 (AU) • Major disk perturbations at • rG = Gm / v(m)2 ~ 35 mo v5-2 (AU)

  40. Direct Accretion Cannibalism Cores Outflows YSOs Disks Stars Fossils Isolated, non-interacting, massive Dense, clustered, interacting Collimated, quasi-steady Wide-angle, impulsive, transient Isolated, stable L Highly clustered (>106 pc-3), intense IR (radio?) flares Accretion, steady, thin Accretion & expanding, transient, thick High density clusters, fast spin, many binaries? Isolated, low density clusters, moderate spin Low dispersion, few runaways till 1st SN High dispersion, young runaways from dynamical interactions

  41. Most Stars Form Near Massive Star Groups • GMCs Spawn 5,000 to 30,000 Stars • in a region less than 100 light years in diameter • Most low mass stars exposed to effects of high • mass stars during their youth • Most Proto-planetary Disks may be destroyed!

  42. Disks in the Orion Nebula • Orion Nebula: D = 1500 light years • 2,000 low mass stars: < 1.5 million years old • Dozen high mass stars (Trapezium): • < 100,000 years old • Destruction of Proto-Planetary Disks

  43. Core of the Orion Nebula(Hubble Space Telescope)

  44. HST 16 HST 10 HST 17 Irradiated proto-planetary disks:

  45. Evaporating disks with jets 182-413 (HST10)

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