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Table 2:

Observed numbers of EMP, CEMP, CNEMP and NEMP stars from the SAGA database for our various selection criteria.

Metallicity
$\log g$ EMP CEMP CNEMP NEMP   CEMP/EMP Additional selection criteria
$[{\rm Fe}/{\rm H}]$         $[{\rm N}/{\rm Fe}]>1$ $[{\rm N}/{\rm Fe}]>0.5$ fraction  
$-2.3\pm0.5$ ${\leq}4$ 308 96       31% only stars with C measured
$-2.3\pm0.5$ ${\leq}4$ 373 96       26% all EMP stars
$-2.3\pm0.5$ ${\leq}4$ 104 88 0 0 7   only stars with C and N measured
$-2.3\pm0.5$ ${\leq}4$ 373 96 0 0 7 26% $\left\{ \begin{array}{c} {\rm C~ and~ N~ measured~ for~(C)NEMPs,}\\
{\rm C~ measured~ for~ CEMPs},\end{array}\right.$
all ${\leq}4$ 779 144 4 14 22 18% ''
$-2.3\pm0.5$ all 479 115 0 0 7 24% ''
all all 1366 177 6 17 23 13% ''
${\leq}2.0$ giants 132 11       $9\pm2\%$ Frebel et al. (2006)
${\leq}2.0$   270 58       ${>}21\pm2\%$ Lucatello et al. (2006)
${\leq}2.0$ giants           $14\pm4\%$ Cohen et al. (2005)

The first line of data counts only stars which have a $[{\rm C}/{\rm Fe}]$ measurement. The second line of data additionally counts stars without measured $[{\rm C}/{\rm Fe}]$ as EMPs, i.e. it is assumed that $[{\rm C}/{\rm Fe}]<1$ for these stars. In the next four lines stars with both measured C and N are used to count (C)NEMP stars while stars with C measured count the CEMP stars.
Also shown are estimates of the CEMP/EMP ratio from Cohen et al. (2005), Frebel et al. (2006) and Lucatello et al. (2006).


Source LaTeX | All tables | In the text

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