Carbon abundances A(C) of CEMP stars as a function of [Fe/H]. The stars in the present paper and in Caffau et al. (2013a) are shown with big and small circles, respectively. The other turn-off stars come from the literature (Sivarani et al. 2006; Frebel et al. 2005, 2006; Thompson et al. 2008; Aoki et al. 2008; Behara et al. 2010; Masseron et al. 2010, 2012; Yong et al. 2013; Cohen et al. 2013; Li et al. 2015). The CEMP-no turn-off stars are represented by filled blue squares. The CEMP-no giants are represented by two symbols: an open blue square for the measured value of the C abundance, and a filled blue square for the empirically corrected (for the first dredge-up) A(C) value. The CEMP-s or -rs stars are indistinctly represented by open red squares, but by open red triangles if they are also Pb-rich. When the Ba abundance is unknown the star is marked with a black cross. The upper limit marked as a violet star is the only “C-normal” star that appears in this plot: SDSS J1029+1729 (Caffau et al. 2012). The solid horizontal (black) lines represent the mean value of the carbon abundance for CEMP stars with [Fe/H] > −3.0 (A(C) = 8.25) and for CEMP stars with [Fe/H] < −3.4 (A(C) = 6.8) as derived by Spite et al. (2013). On the upper A(C)-band all the stars but four (HE 0007-1832, HE 022-4831, SDSS J0036-1043, and CS 22958-42) are Ba-rich. On the contrary, on the lower A(C)-band all the stars are CEMP-no.
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.