Thursday, November 3, 2011

1111.0296 (András Gáspár et al.)

Modeling Collisional Cascades In Debris Disks: Steep Dust-Size Distributions    [PDF]

András Gáspár, Dimitrios Psaltis, George H. Rieke, Feryal Özel
We explore the evolution of the mass distribution of dust in collision-dominated debris disks, using the collisional code introduced in our previous paper. We analyze the equilibrium distribution and its dependence on model parameters by evolving over 100 models to 10 Gyr. With our numerical models, we show that systems reach collisional equilibrium with a mass distribution that is steeper than the ones given by earlier analytic or current numerical methods. Our model yields a steady state slope of n(m) ~ m^{-1.88} [n(a) ~ a^{-3.65}]. This steeper solution has observable effects in the submillimeter and millimeter wavelength regimes of the electromagnetic spectrum. We assemble data for nine debris disks that have been observed at these wavelengths and, using a simplified absorption efficiency model, show that the predicted slope of the particle mass distribution generates SEDs that are in agreement with the observed ones.
View original: http://arxiv.org/abs/1111.0296

No comments:

Post a Comment