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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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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 Angular momentum transport Evolution of the solids National Aeronautics and Space Administration
Hartigan et al. 1995 / Antoniucci et al. 2008 National Aeronautics and Space Administration
McKee & Ostriker 2007 National Aeronautics and Space Administration
Pyo et al. 2005 National Aeronautics and Space Administration
Zinnecker et al. 1998 National Aeronautics and Space Administration
Takami et al. 2001 National Aeronautics and Space Administration
Burrows et al. 1996 National Aeronautics and Space Administration
C. Lada 1985 National Aeronautics and Space Administration
Girart et al. 2006 National Aeronautics and Space Administration
Tamura et al. 1999 National Aeronautics and Space Administration
T. Ray et al. 1997 National Aeronautics and Space Administration
Johns-Krull 2007 National Aeronautics and Space Administration
Ferreira et al. 2006 National Aeronautics and Space Administration
Spruit 1996 National Aeronautics and Space Administration
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
Y. Kato 2004 National Aeronautics and Space Administration
Outflow-Driven Turbulence 1 Nakamura & Li 2007 National Aeronautics and Space Administration
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
Basic Disk Properties National Aeronautics and Space Administration
Hartmann & Kenyon 1996 National Aeronautics and Space Administration
M. Simon et al. 2000 National Aeronautics and Space Administration
Andrews & Williams 2007 National Aeronautics and Space Administration
Andrews & Williams 2007 National Aeronautics and Space Administration
Origins of the Surface Density Profile In steady-state Shakura-Sunyaev a-disk, if irradiation controls the temperature profile. National Aeronautics and Space Administration
Weidenschilling 1977 National Aeronautics and Space Administration
Dullemond et al. 2007 National Aeronautics and Space Administration
Dullemond et al. 2007 National Aeronautics and Space Administration
Dullemond et al. 2007 National Aeronautics and Space Administration
Bergin et al. 2007 National Aeronautics and Space Administration
K. R. Bell et al. 1995 National Aeronautics and Space Administration
Hartmann et al. 1993 National Aeronautics and Space Administration
Angular Momentum Transport National Aeronautics and Space Administration
1. Gravitational Instability National Aeronautics and Space Administration
1. Gravitational Instability National Aeronautics and Space Administration
Small disturbances grow if National Aeronautics and Space Administration
Gammie 2001 National Aeronauticsand Space Administration
Gammie 2001 National Aeronautics and Space Administration
With slower cooling, instability leads to sustained accretion. Mejia et al. 2005 National Aeronautics and Space Administration
2. Magneto-Rotational Turbulence Balbus & Hawley 1991 National Aeronautics and Space Administration
2. Magneto-Rotational Turbulence Balbus & Hawley 1991 National Aeronautics and Space Administration
Gammie 1996 National Aeronautics and Space Administration
Three Ways to Lose Magnetic Flux National Aeronautics and Space Administration
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
Wardle 2007 National Aeronautics and Space Administration
MRI turbulence requires Sano & Stone 2002b National Aeronautics and Space Administration
1 mm Grains National Aeronautics and Space Administration
No Grains National Aeronautics and Space Administration