Formation, early evolution, and gravitational stability of protoplanetary disks

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

43

Accretion Disks, Gravitation Theory, Hydrodynamics, Planetary Evolution, Planetary Gravitation, Protoplanets, Systems Stability, Star Formation, Viscous Flow

Scientific paper

The formation, viscous evolution, and gravitational stability of protoplanetary disks are investigated. The formation process is parameterized by the angular velocity of the molecular cloud core omega, while the viscous evolution is parameterized by the viscosity parameter alpha in the disk; in this study we consider a range of (0.4-6) x 10-14/s for omega and from 10-5 to 10-1 for alpha. The axisymmetric gravitational stabilities of the disks are checked using Toomre's criterion. The resulting disk surface temperature distribution, (d log Ts/d log R) approximately = -0.6 (R is the cylindrical radius), can be attributed to two heating sources: the viscous heating dominant in the inner disk region, and the accretion shock heating dominant in the outer disk region. This surface temperature distribution matches that observed in many disks around young stellar objects. During the infall stage, disks with alpha less than 10-1.5 become gravitationally unstable independent of omega. The gravitational instabilities occur at radii ranging from 5 to 40 AU. The ratio of the disk mass to the central star mass ranges from 0.2 to 0.5 at the times of instability, about 4 x 10-5 x (omega/10-14/s)-0.67 yr. Most disks with low alpha and high omega become gravitationally unstable during their formation phase.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Formation, early evolution, and gravitational stability of protoplanetary disks does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Formation, early evolution, and gravitational stability of protoplanetary disks, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Formation, early evolution, and gravitational stability of protoplanetary disks will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1013917

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.