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High-resolution spectroscopy of V854 Cen in decline - Absorption and emission lines of C_2 molecules

N. Kameswara Rao·David L. Lambert
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Abstract

High-resolution optical spectra of the R Coronae Borealis (RBC) star V854 Centauri in the early stages of a decline show, in addition to the features reported for other RCBs in decline, narrow absorption lines from the C_2 Phillips system. The low rotational temperature, T_rot = 1150K, of the C_2 ground electronic state suggests the cold gas is associated with the developing shroud of carbon dust. These absorption lines were not seen at a fainter magnitude on the rise from minimum light nor at maximum light. This is the first detection of cold gas around a RCB star.

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N. Kameswara Rao, David L. Lambert. 2000-02-10. High-resolution spectroscopy of V854 Cen in decline - Absorption and emission lines of C_2 molecules. https://doi.org/10.1046/j.1365-8711.2000.03397.x

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