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SUMMARY:Review - protostellar disk observations - Hartmann \, L (Michigan)
DTSTART:20090817T090000Z
DTEND:20090817T100000Z
UID:TALK19514@talks.cam.ac.uk
CONTACT:Mustapha Amrani
DESCRIPTION:Rapid progress is being made in developing observational const
 raints on the structure and evolution of protoplanetary disks\, primarily 
 due advances in spectral sensitivity due to the Spitzer Space Telescope an
 d improvements in spatial resolution from mm-wave interferometry. Unfortun
 ately there still are considerable uncertainties in the masses and mass di
 stributions of disks. I will review the observational limits we now have o
 n disk masses\, the evidence for dust growth and settling in these disks\,
  and the increasingly common indications of inner disk clearing at early e
 volutionary times (~ 1 Myr). I will then argue that the time-dependence of
  disk accretion in the protostellar phase strongly suggests that something
  like a dead zone or high-surface-density\, low-viscosity\, region exists 
 in inner disks\, at least initially\, providing the conditions for more ra
 pid formation of relatively massive bodies.
LOCATION:Seminar Room 1 Newton Institute
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