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arXiv · 1407.3696

High-resolution optical spectroscopy of the R Coronae Borealis star V532 Ophiuchi at maximum light

N. Kameswara Rao·David L. Lambert·Vincent M. Woolf·B. P. Hema
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Abstract

High-resolution optical spectra of the R Coronae Borealis (RCB) star V532 Oph at light maximum are discussed. The absolute visual magnitude M_V of the star is found to be -4.9 \pm 0.5. The elemental abundances suggest the star belongs to the majority class of RCB stars but is among the most O-poor of this class with mild enhancements of heavy elements Y, Zr, Ba and La. The C_2 Swan bands are weak in V532 Oph relative to R CrB. Other aspects of the high-resolution spectrum confirm that V532 Oph is representative of majority RCBs, i.e., the radial velocity is variable, circumstellar material is present and the photosphere feeds a high-velocity stellar wind.

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N. Kameswara Rao, David L. Lambert, Vincent M. Woolf, B. P. Hema. 2014-07-14. High-resolution optical spectroscopy of the R Coronae Borealis star V532 Ophiuchi at maximum light. https://doi.org/10.1086/678129

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