2010/02/09 by Currie, Thayne
#Astrophysics of Galaxies (astro-ph.GA) #Earth and Planetary Astrophysics (astro-ph.EP) #FOS: Physical sciences #Solar and Stellar Astrophysics (astro-ph.SR)
paper · doi:10.48550/arxiv.1002.1715
I describe new constraints on the lifetimes and morphologies of transitional protoplanetary disks from observations of 1--10 Myr old stars with the Spitzer Space Telescope. New Spitzer results clearly show evidence for two kinds of transitional disks and thus two main disk evolutionary pathways: disks which form an inner hole/gap and clear from the inside out and disks that deplete more homologously. Analyzing the disk populations of 1--10 Myr old clusters such as Taurus, IC 348, NGC 2362, and η Cha show that the mean transitional disk lifetime must be an appreciable fraction of the mean protoplanetary disk lifetime: ≈ 1 Myr out of 3--5 Myr. The varieties of transitional disk SEDs and correlations with other disk diagnostics are consistent with multiple mechanisms responsible for clearing disks.