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Title:
Gas disk evolution and disk dispersal
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Authors:
E. F. van Dishoeck,
Leiden Observatory
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Abstract:
This talk will review the chemical and physical evolution of the gas in disks from an observational and theoretical perspective. First, observational tracers of the gas mass in disks from infrared (CO, H2, ...) and millimeter (CO, C+, C) observations will be summarized and their advantages and drawbacks discussed. Second, the proposed mechanisms for gas disk dispersal will be mentioned and compared, including viscous accretion and photoevaporation by the EUV and FUV radiation from young star(s).
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