Abundance Analyses of the New R Coronae Borealis Stars: ASAS-RCB-8 and ASAS-RCB-10
Kamath, Devika; Pandey, Gajendra; Kameswara Rao, N.; Hema, B. P.; Lambert, David; Woolf, Vincent M.
India, Australia, Belgium, United States
Abstract
Abundance analyses of the two newly discovered R Coronae Borealis (RCB) stars ASAS-RCB-8 and ASAS-RCB-10 were conducted using high-resolution optical spectra and model atmospheres. Their chemical compositions place the pair among the majority class of RCBs. ASAS-RCB-10 is one of the most N-poor majority RCBs with an above average O abundance. Relative to ASAS-RCB-10, ASAS-RCB-8 is H poor by 1.6 dex, O-poor by 0.7 dex but N-rich by 0.8 dex suggesting a higher contamination by CNO-cycled material.