Paper: astro-ph/0506154
Date: Tue, 7 Jun 2005 22:01:39 GMT (193kb)

Title: Near infrared and the inner regions of protoplanetary disks

Authors: Dejan Vinkovic, Zeljko Ivezic, Tomislav Jurkic and Moshe Elitzur
Comments: 14 pages, 10 figures, submitted to ApJ
\\
We examine the ``puffed-up inner disk'' model (Dullemond, Dominik & Natta
2001), proposed for explaining the near-IR excess radiation from Herbig Ae/Be
stars. Detailed model re-computations and comparison with the observed
distribution of near-IR excess show that the model requires fine tuning of free
parameters. In particular, only perfectly gray dust opacity can produce the
observed near-IR excess, yet such dust is in conflict with the observed
10$\mu$m spectral feature. We find that an alternative model consisting of a
compact ($\sim$ 10 AU) tenuous dusty halo around the disk inner regions readily
explains the observed near-IR excess. Furthermore, this model also resolves the
puzzling relationship noted by Monnier and Millan-Gabet (2002) between
luminosity and the interferometric inner radii of disks.

\\ ( http://arXiv.org/abs/astro-ph/0506154 , 193kb)