Astronomy and Astrophysics – Astrophysics
Scientific paper
Mar 2006
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006ecgou..28..155b&link_type=abstract
"Formation planétaire et exoplanètes, Ecole thématique du CNRS, Goutelas (Loire), 23 - 27 mai 2005 Edited by J.-L. Halbwachs, D.
Astronomy and Astrophysics
Astrophysics
Debris Disk
Scientific paper
Debris disks are dusty and gaseous circumstellar disks orbiting stars with ages ranging from 10(7 ) yr to a few 10(8 ) yr. In contrast to genuine protoplanetary disk, they are optically thin, and are characterized by a very small amount of gas. As a consequence, their dynamics is basically gravitational. They are mainly observed in scattered light in the near infrared and/or in thermal emission at longer wavelengths. About 12 disks of this kind are known today, but their number increases rapidly thanks to the improvement of the detection techniques and instruments.
What is seen in these disks is dust. Observing a scattered light profile in a debris disk, one wants to derive the spatial distribution of the dust particles. The inversion method is close to a deprojection technique. Typically (e.g., in the bp\ disk), the surface density decreases as r(-1) up to a given distance (120 AU in the bp\ disk) and falls off more steeply (˜~ r(-4) ) further out.
Dust particles in debris disks are usually subject to an intense radiation pressure that drastically affects their dynamics. Combined with collisions, it contributes to quickly erode the dust population by removing the smallest grains. Hence the dust population must be sustained by a large population of colliding and/or evaporating planetesimals. Once produced by the parent bodies, the dust particles diffuse further out in the disk thanks to radiation pressure, or wind pressure in disks orbiting late-type stars.
Nearly all debris disks that have been imaged exhibit various structures and asymetries, such as gaps, clumps, warps, and spiral arms. These structures are usually thought to originate in the distribution of the parent bodies, and to be due to gravitational perturbations by hidden planets and/or stellar companions, involving direct or secular perturbations, or interaction with mean-motion resonances. A detailed analysis of the observed structures in a given disk combined with dynamical simulations can in principle give access to the suspected planetary system. Valuable constraints have been derived in some cases. The solution is nevertheless not unique in general and the analysis is complicated by the fact that we only observe the dust particles and not the planetesimal population directly.
Beust Hervé
Halbwachs Jean-Louis
No associations
LandOfFree
Modélisation des disques de débris 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 Modélisation des disques de débris, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Modélisation des disques de débris will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1136115