Dust distribution in gas disks. 2. Self induced ring formation through a clumping instability

Feb, 2005
24 pages
Published in:
  • Astrophys.J. 632 (2005) 1113-1121
e-Print:

Citations per year

200520072009201120131524
Abstract: (arXiv)
Debris rings of dust are found around young luminous stars such as HR4796A and HD141569. Some of these entities have sharp edges and gaps which have been interpreted as evidence for the presence of shepherding and embedded planets. Here we show that gaps and sharp edges in the debris disks of dust can also be spontaneously self generated if they are embedded in optically thin regions of gaseous disks. This clumping instability arises in regions where an enhancement in the dust density leads to local gas temperature and pressure increases. Consequently, the relative motion between the gas and the dust is modified. The subsequent hydrodynamic drag on the dust particles leads to further enhancement of their concentration. We show that this process is linearly unstable and leads to the formation of ring-like structures within the estimated life time of such young objects. Once the gas is removed (e.g. by photo evaporation) the structures are ``frozen'' and will persist, even when the gas might not be observable anymore.
  • circumstellar matter
  • planetary systems
  • stars: formation