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Protostellar Disks: Birth, Life and Death

National Aeronautics and Space Administration. Protostellar Disks: Birth, Life and Death. Neal Turner Jet Propulsion Laboratory, California Institute of Technology. The Life of Protostellar Disks. Jets and Winds Basic disk properties

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Protostellar Disks: Birth, Life and Death

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  1. National Aeronautics and Space Administration Protostellar Disks: Birth, Life and Death Neal Turner Jet Propulsion Laboratory, California Institute of Technology

  2. The Life of Protostellar Disks Jets and Winds Basic disk properties Angular momentum transport Evolution of the solids National Aeronautics and Space Administration

  3. National Aeronautics and Space Administration

  4. Hartigan et al. 1995 / Antoniucci et al. 2008 National Aeronautics and Space Administration

  5. McKee & Ostriker 2007 National Aeronautics and Space Administration

  6. Pyo et al. 2005 National Aeronautics and Space Administration

  7. Zinnecker et al. 1998 National Aeronautics and Space Administration

  8. Takami et al. 2001 National Aeronautics and Space Administration

  9. Burrows et al. 1996 National Aeronautics and Space Administration

  10. C. Lada 1985 National Aeronautics and Space Administration

  11. Girart et al. 2006 National Aeronautics and Space Administration

  12. Tamura et al. 1999 National Aeronautics and Space Administration

  13. T. Ray et al. 1997 National Aeronautics and Space Administration

  14. Johns-Krull 2007 National Aeronautics and Space Administration

  15. Ferreira et al. 2006 National Aeronautics and Space Administration

  16. Spruit 1996 National Aeronautics and Space Administration

  17. Size of the Launching Region? Jet power = Rate of work done against the magnetic torque = (Footpoint orbital frequency) x (Angular momentum flux): Infer launching region lies 0.3 to 4 AU from the star. Assumes energy and momentum conserved along streamlines. Anderson et al. 2003 National Aeronautics and Space Administration

  18. Y. Kato 2004 National Aeronautics and Space Administration

  19. Outflow-Driven Turbulence 1 Nakamura & Li 2007 National Aeronautics and Space Administration

  20. Outflow-Driven Turbulence 2 Cloud kinetic energy vT2dissipates on a crossing time R/vT, so the outflows can provide the stirring if i.e., if the outflow kinetic luminosity is greater than the dissipation rate in the gas associated with the star. With R=10 pc, vT=10 km s-1, f=0.01, vJ=300 km s-1 and jet mass flow rate 10-7 Solar masses per year, the outflows are sufficient to power the turbulence. National Aeronautics and Space Administration

  21. Basic Disk Properties National Aeronautics and Space Administration

  22. Hartmann & Kenyon 1996 National Aeronautics and Space Administration

  23. M. Simon et al. 2000 National Aeronautics and Space Administration

  24. Andrews & Williams 2007 National Aeronautics and Space Administration

  25. Andrews & Williams 2007 National Aeronautics and Space Administration

  26. Origins of the Surface Density Profile In steady-state Shakura-Sunyaev a-disk, if irradiation controls the temperature profile. National Aeronautics and Space Administration

  27. Weidenschilling 1977 National Aeronautics and Space Administration

  28. Dullemond et al. 2007 National Aeronautics and Space Administration

  29. Dullemond et al. 2007 National Aeronautics and Space Administration

  30. Dullemond et al. 2007 National Aeronautics and Space Administration

  31. Bergin et al. 2007 National Aeronautics and Space Administration

  32. K. R. Bell et al. 1995 National Aeronautics and Space Administration

  33. Hartmann et al. 1993 National Aeronautics and Space Administration

  34. Angular Momentum Transport National Aeronautics and Space Administration

  35. 1. Gravitational Instability National Aeronautics and Space Administration

  36. 1. Gravitational Instability National Aeronautics and Space Administration

  37. Small disturbances grow if National Aeronautics and Space Administration

  38. Gammie 2001 National Aeronauticsand Space Administration

  39. Gammie 2001 National Aeronautics and Space Administration

  40. With slower cooling, instability leads to sustained accretion. Mejia et al. 2005 National Aeronautics and Space Administration

  41. 2. Magneto-Rotational Turbulence Balbus & Hawley 1991 National Aeronautics and Space Administration

  42. 2. Magneto-Rotational Turbulence Balbus & Hawley 1991 National Aeronautics and Space Administration

  43. National Aeronautics and Space Administration

  44. Gammie 1996 National Aeronautics and Space Administration

  45. Three Ways to Lose Magnetic Flux National Aeronautics and Space Administration

  46. Ionization Processes At 1 AU in the minimum mass Solar nebula Stellar X-Rays Interstellar Cosmic Rays Short-Lived Radionuclides Midplane ionisation is weak! Long-Lived Radionuclides National Aeronautics and Space Administration

  47. Wardle 2007 National Aeronautics and Space Administration

  48. MRI turbulence requires Sano & Stone 2002b National Aeronautics and Space Administration

  49. 1 mm Grains National Aeronautics and Space Administration

  50. No Grains National Aeronautics and Space Administration

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