A search for interstellar gas-phase CO2? Gas: solid state abundance ratios
نویسنده
چکیده
We present searches for gas–phase CO2 features in the ISO–SWS infrared spectra of four deeply embedded massive young stars, which all show strong solid CO2 absorption. The abundance of gas–phase CO2 is at most 2: 10 7 with respect to H2, and is less than 5% of that in the solid phase. This is in strong contrast to CO, which is a factor of 10–100 more abundant in the gas than in solid form in these objects. The gas/solid state ratios of CO2, CO and H2O are discussed in terms of the physical and chemical state of the clouds.
منابع مشابه
A search for interstellar gas – phase CO 2 ? Gas / solid state abundance ratios
We present searches for gas–phase CO2 features in the ISO–SWS infrared spectra of four deeply embedded massive young stars, which all show strong solid CO2 absorption. The abundance of gas–phase CO2 is at most 2: 10 7 with respect to H2, and is less than 5% of that in the solid phase. This is in strong contrast to CO, which is a factor of 10–100 more abundant in the gas than in solid form in th...
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