Debris disks are optically thin, almost gas-free dusty disks observed arounda significant fraction of main-sequence stars older than about 10 Myr. Since the circumstellar dust is short-lived, the very existence of the...Debris disks are optically thin, almost gas-free dusty disks observed arounda significant fraction of main-sequence stars older than about 10 Myr. Since the circumstellar dust is short-lived, the very existence of these disks is considered as evi-dence that dust-producing planetesimals are still present in mature systems, in whichplanets have formed – or failed to form – a long time ago. It is inferred that theseplanetesimals orbit their host stars at asteroid to Kuiper-belt distances and continuallysupply fresh dust through mutual collisions. This review outlines observational techniques and results on debris disks, summarizes their essential physics and theoreticalmodels, and then places them into the general context of planetary systems, uncovering interrelations between the disks, dust parent bodies, and planets. It is shownthat debris disks can serve as tracers of planetesimals and planets and shed light onthe planetesimal and planet formation processes that operated in these systems in thepast.展开更多
基金Support by the German Research Foundation (Deutsche Forschungs-gemeinschaft, DFG), project number Kr 2164/8–1by the Deutscher Akademischer Austauschdienst(DAAD), project D/0707543by the International Space Science Institute in Bern, Switzerland("Exozodiacal Dust Disks and Darwin" working group
文摘Debris disks are optically thin, almost gas-free dusty disks observed arounda significant fraction of main-sequence stars older than about 10 Myr. Since the circumstellar dust is short-lived, the very existence of these disks is considered as evi-dence that dust-producing planetesimals are still present in mature systems, in whichplanets have formed – or failed to form – a long time ago. It is inferred that theseplanetesimals orbit their host stars at asteroid to Kuiper-belt distances and continuallysupply fresh dust through mutual collisions. This review outlines observational techniques and results on debris disks, summarizes their essential physics and theoreticalmodels, and then places them into the general context of planetary systems, uncovering interrelations between the disks, dust parent bodies, and planets. It is shownthat debris disks can serve as tracers of planetesimals and planets and shed light onthe planetesimal and planet formation processes that operated in these systems in thepast.
