SWS observations of solid CO2 in molecular clouds
نویسندگان
چکیده
We report absorption features of solid CO2 stretching and bending modes in several lines of sight, including embedded young stellar objects and the Galactic Center source Sgr A*. The overall CO2 abundance in ices is 15% relative to H2O. Profile shapes are consistent with the presence of grain mantles with distinct polar (H2O-rich) and nonpolar (CO or CO2-rich) layers. In addition to the normal isotopic form, we report detection of the stretching mode of CO2; the 12C/13C ratio is consistent with terrestrial and interstellar values.
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