Water Vapor in Carbon-rich Asymptotic Giant Branch Stars from the Vaporization of Icy Orbiting Bodies

  title={Water Vapor in Carbon-rich Asymptotic Giant Branch Stars from the Vaporization of Icy Orbiting Bodies},
  author={K. E. Saavik Ford and David A. Neufeld},
  journal={The Astrophysical Journal Letters},
  pages={L113 - L116}
We argue that the presence of water vapor in the circumstellar outflow of a carbon-rich asymptotic giant branch (AGB) star is potentially a distinctive signature of extrasolar cometary systems. Detailed models show that at suitable distances from the star, water ice can survive well into the carbon-rich AGB phase; water vapor abundances as large as 10-6 could result from the vaporization of a collection of orbiting icy bodies with a total mass comparable to what might have been originally… 


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