How Bright Are the R Coronae Borealis Stars?
G. C. Clayton (LSU), D. L. Welch (McMaster), D. Kilkenny (SAAO), C. Alcock, D. Alves, K. H. Cook, S. L. Marshall, D. Minniti (LLNL/CfPA), D. P. Bennett (Notre Dame/CfPA), R. A. Allsman (ANU), A. Becker, M. R. Pratt, C. W. Stubbs (UW/CfPA), T. S. Axelrod, K. C. Freeman, B. A. Peterson, A. W. Rodgers (MSSSO), P. J. Quinn (ESO), K. Griest, J. A. Guern, M. J. Lehner (CfPA/UCSD), W. Sutherland (Oxford) We report the discovery of several new R Coronae Borealis (RCB) stars in the Large Magellanic Cloud (LMC) using the MACHO project photometry database. The identification of at least six new stars has now been confirmed spectroscopically. Five are cool RCB stars (T_eff\sim 5000 K) characterized by very strong Swan bands of C_2 and violet bands of CN, and weak or absent Balmer lines, G-band and ^12C^13C bands. The sixth star is an example of a hot RCB star of which only 3 were previously known to exist in the Galaxy and none in the LMC. All of the stars have shown deep declines of \Delta V \ge
