ar X iv : a st ro - p h / 04 07 15 3 v 1 7 J ul 2 00 4 Detection of Formaldehyde Towards the Extreme Carbon Star IRC + 10216
نویسندگان
چکیده
We report the detection of H2CO (formaldehyde) around the carbon-rich AGB star, IRC+10216. We find a fractional abundance with respect to molecular hydrogen of x(H2CO) = 1.3 +1.5 −0.8 × 10 . This corresponds to a formaldehyde abundance with respect to water vapor of x(H2CO)/x(H2O) = (1.1±0.2)×10 , in line with the formaldehyde abundances found in Solar System comets, and indicates that the putative extrasolar cometary system around IRC+10216 may have a similar chemical composition to Solar System comets. However, we also failed to detect CH3OH (methanol) around IRC+10216 and our upper limit of
منابع مشابه
ar X iv : a st ro - p h / 03 02 10 3 v 1 5 F eb 2 00 3 Detection of OH Towards the Extreme Carbon Star IRC + 10216
We report the detection of the 1665 and 1667MHz main lines of OH (hydroxyl) and upper limits on the 1612MHz satellite line of OH towards the carbonrich AGB star, IRC+10216. We find a beam averaged fractional abundance x(OH) ∼ 4 × 10. This detection supports the identification by Melnick et al. (2001) of the 110−101 transition of water vapor with a 556.936GHz emission feature detected towards IR...
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