منابع مشابه
Cold CO Gas in Protoplanetary Disks
In a disk around DM Tau, previous observation of CO (J = 2− 1 and 1− 0 transitions) derived the CO gas temperature of ∼ 13−20K, which is lower than the sublimation temperature of CO (20 K). We argue that the existence of such cold CO can be explained by a vertical mixing of disk material. As the gas is transported from a warm layer to a cold layer, CO is depleted onto dust grains with a timesca...
متن کاملProtoplanetary Gas Disks in the Far Infrared
The physical and chemical conditions in young protoplanetary disks set the boundary conditions for planet formation. Although the dust in disks is relatively easily detected as a far-IR photometric “excess” over the expected photospheric emission, much less is known about the gas phase. It seems clear that an abrupt transition from massive optically thick disks (gas–rich structures where only ∼...
متن کاملGas-phase CO in protoplanetary disks: A challenge for turbulent mixing
This is the first paper in a series where we study the influence of turbulent diffusion and advective transport on the chemical evolution of protoplanetary disks, using a 2D flared disk model and a 2D mixing gas-grain chemical code with surface reactions. A first interesting result concerns the abundance of gasphase CO in the outer regions of protoplanetary disks. In this Letter we argue that t...
متن کاملEvidence for CO depletion in the inner regions of gas-rich protoplanetary disks
Aims. We investigate the physical properties and spatial distribution of Carbon Monoxide (CO) gas in the disks around the Herbig Ae/Be stars HD 97048 and HD 100546. Methods. Using high-spectral-resolution 4.588−4.715 μm spectra containing fundamental CO emission taken with CRIRES on the VLT, we probe the circumstellar gas and model the kinematics of the emission lines. By using spectro-astromet...
متن کاملTurbulent-diffusion Mediated CO Depletion in Weakly Turbulent Protoplanetary Disks
Volatiles, especially CO, are important gas tracers of protoplanetary disks (PPDs). Freeze-out and sublimation processes determine their division between gas and solid phases, which affects both which disk regions can be traced by which volatiles, and the formation and composition of planets. Recently, multiple lines of evidence have suggested that CO is substantially depleted from the gas in t...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2007
ISSN: 0004-637X,1538-4357
DOI: 10.1086/512674