Dust dissipation timescales of protoplanetary disks and debris disks
Abstract
The far-infrared excess of stars with protoplanetary disks and debris disks is expected to provide us with key information on dust dissipation process in the outer disks. In order to reveal the typical behavior of the disks including objects fainter than the current survey limit, we stacked far-infrared images cut out from the image of AKARI all-sky survey in the 90 micrometers band (WIDE-S) on the basis of known object positions. We carried out two type of studies: one is the study on protoplanetary disks based on observations of T Tauri stars, and the other is the study on debris disks based on observations of A-type main sequence stars. Our studies show that, as disks evolve from protoplanetary disks to debris disks, the dust dissipation timescale becomes longer. This suggests that with disk evolution the dominant dust component changes from primordial dust, which remains small without growing into planetesimals, to secondary dust, which is formed by collisional destruction of planetesimals.
- Publication:
-
The Cosmic Wheel and the Legacy of the AKARI Archive: From Galaxies and Stars to Planets and Life
- Pub Date:
- March 2018
- Bibcode:
- 2018cwla.conf..313M
- Keywords:
-
- Star-Formation: protoplanetary disks;
- circumstellar matter