R Coronae Borealis Stars at Minimum Light -- UW Cen

Abstract

Two high-resolution optical spectra of the R Coronae Borealis star UW Cen in decline are discussed. A spectrum from mid-1992 when the star had faded by three magnitudes shows just a few differences with the spectrum at maximum light. The ubiquitous sharp emission lines seen in R CrB at a similar drop below maximum light are absent. In contrast, a spectrum from mid-2002 when the star was five magnitudes below maximum light shows an array of sharp emission lines and a collection of broad emission lines. Comparisons are made with spectra of R CrB obtained during the deep 1995-1996 minimum. The many common features are discussed in terms of a torus-jet geometry.

8 pages including 9 figures, Accepted for publication in MNRAS

References in corpus (2)

• Winds in R Coronae Borealis Stars
• High-resolution spectroscopy of QY Sge -- An obscured RV Tauri variable?

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