All Figures

$\begin{figure} \par\includegraphics[width=6.5cm,clip]{H4268f1.eps} \end{figure}$ Figure 1: Phased V light curves of M 3/V 9 (dots) and UW Gru (crosses). The magnitudes of UW Gru are shifted to match the magnitudes of M 3/V 9. The identity of the light curves' shapes indicates close similarity of the objects that have similar periods and colours. Consequently, no significant metallicity difference between these stars can be real.
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In the text

$\begin{figure} \par\includegraphics[width=7.4cm,clip]{H4268f2.eps} \end{figure}$ Figure 2: Spectroscopic vs. photometric [Fe/H] of 18 RRab stars in M 3. Dotted lines are the direct and inverse linear regression fits to the data. The correlation between the spectroscopic and photometric metallicities seems to be significant. As the two different measures of the metallicities are basically independent, their correlation indicates that a metallicity range of the M 3 variables is indeed detected.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{H4268f3.eps} \end{figure}$ Figure 3: Histogram of correlation coefficients (r) of 10 000 Monte-Carlo simulations of 18 [Fe/H] $_{\rm spect}$ and [Fe/H] $_{\rm phot}$ pairs. a) No metallicity spread is assumed, the standard deviations of the data are 0.22 and 0.13 dex, respectively. b) The data range over 0.34 dex in metallicity with 0.18 and 0.11 dex standard deviations. Arrows indicate the regression coefficient between the measured spectroscopic and photometric metallicities.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{H4268f4.eps} \end{figure}$ Figure 4: Absolute magnitudes versus spectroscopic and photometric metallicities of M 3 RRab stars. ${M_V = \langle V\rangle_{\rm int} - 15.12}$ mag (Harris 1996). Lines indicate one of the theoretical ZAHB relations (Caloi et al. 1997). For the [Fe/H] $_{\rm phot}$ values at the different metallicities the faintest stars (which are likely on the ZAHB) indicate a similar trend of M_V with metallicity as expected, if the metallicity range is real. The brightest star V 60 has the longest period (0.77 d) and possibly is already in an evolved stage of the HB evolution. The second brightest among the spectroscopic sample is V 202 which RR Lyrae classification is uncertain. The less convincing evidence of an M_V - [Fe/H] relation for the spectroscopic values is possibly due to the larger errors in the [Fe/H] $_{\rm spect}$ values.
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In the text

$\begin{figure} \par\includegraphics[width=6.5cm,clip]{H4268f1.eps} \end{figure}$	Figure 1: Phased V light curves of M 3/V 9 (dots) and UW Gru (crosses). The magnitudes of UW Gru are shifted to match the magnitudes of M 3/V 9. The identity of the light curves' shapes indicates close similarity of the objects that have similar periods and colours. Consequently, no significant metallicity difference between these stars can be real.
Open with DEXTER