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arXiv · 0810.2729

Detection of C5N- and vibrationally excited C6H in IRC +10216

J. Cernicharo·M. Guélin·M. Agúndez·M. C. McCarthy·P. Thaddeus
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Abstract

We report the detection in the envelope of the C-rich star IRC +10216 of four series of lines with harmonically related frequencies: B1389, B1390, B1394 and B1401. The four series must arise from linear molecules with mass and size close to those of C6H and C5N. Three of the series have half-integer rotational quantum numbers; we assign them to the 2Delta and 2Sigma vibronic states of C6H in its lowest (v_11) bending mode. The fourth series, B1389, has integer J with no evidence of fine or hyperfine structure; it has a rotational constant of 1388.860(2) MHz and a centrifugal distortion constant of 33(1) Hz; it is almost certainly the C5N- anion.

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J. Cernicharo, M. Guélin, M. Agúndez, M. C. McCarthy, P. Thaddeus. 2008-10-15. Detection of C5N- and vibrationally excited C6H in IRC +10216. https://doi.org/10.1086/595583

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