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

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.

5 pages, 5 figures, accepted for publication by Monthly Notices of the Royal Society of Astronomy

References in corpus (2)

• The triple-shell structure and collimated outflows of the planetary nebula NGC 6891
• The fall and rise of V854 Centauri: long-term ultraviolet spectroscopy of a highly-active R Coronae Borealis star

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• High-resolution spectroscopy of the R Coronae Borealis Star V Coronae Australis
• Dust around R Coronae Borealis stars: I. Spitzer/IRS observations
• R Coronae Borealis at the 2003 Light Minimum
• R Coronae Borealis Stars at Minimum Light -- UW Cen