All Figures

$\begin{figure} \par\includegraphics[width=17cm,clip]{3280fig1.ps} \end{figure}$ Figure 1: Normalised optical spectra (grey lines) of PG 1159 stars and the sdO star (bottom-most spectrum) and model atmospheres (black lines), ordered by decreasing effective temperature. Object names are printed on the left, effective temperatures and logarithmic surface gravities on the right. SDSS J144734.12 +572053.1 was observed twice on different plates and slightly different temperatures are derived, however, within our error estimate.
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In the text

$\begin{figure} \par\includegraphics[width=17cm,clip]{3280fig2.ps} \end{figure}$ Figure 2: Normalised optical spectra (grey lines) of DO white dwarfs and model atmospheres (black lines), ordered by decreasing effective temperature. Object names are printed on the left, effective temperatures and logarithmic surface gravities on the right. The spectra of the hottest stars are dominated by He II absorption lines, while increasing line strengths of He I are observed with decreasing temperature.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{3280fig3.ps} \end{figure}$ Figure 3: Positions of the new PG 1159 stars (with error bars) compared to evolutionary tracks from Blöcker (1995), Schönberner (1983) (dashed lines) and Wood & Faulkner (1986). Labels: mass in $M_{\small{\odot}}$ .
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{3280fig4.ps} \end{figure}$ Figure 4: Positions of DO white dwarfs compared with evolutionary tracks from Wood (1995). The triangles represent the 19 hitherto known DOs (see Dreizler et al. 1997; Werner et al. 2004; Dreizler & Werner 1996).
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{3280fig5.ps} \end{figure}$ Figure 5: Mass distribution (bin = 0.1 $M_{\odot }$ ) of all known DO white dwarfs. The region below the back line represents masses of stars from this work while the area above the line shows results from Dreizler & Werner (1996) and Dreizler et al. (1997).
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{3280fig3.ps} \end{figure}$	Figure 3: Positions of the new PG 1159 stars (with error bars) compared to evolutionary tracks from Blöcker (1995), Schönberner (1983) (dashed lines) and Wood & Faulkner (1986). Labels: mass in $M_{\small{\odot}}$ .
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$\begin{figure} \par\includegraphics[width=8.8cm,clip]{3280fig4.ps} \end{figure}$	Figure 4: Positions of DO white dwarfs compared with evolutionary tracks from Wood (1995). The triangles represent the 19 hitherto known DOs (see Dreizler et al. 1997; Werner et al. 2004; Dreizler & Werner 1996).
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$\begin{figure} \par\includegraphics[width=8.8cm,clip]{3280fig5.ps} \end{figure}$	Figure 5: Mass distribution (bin = 0.1 $M_{\odot }$ ) of all known DO white dwarfs. The region below the back line represents masses of stars from this work while the area above the line shows results from Dreizler & Werner (1996) and Dreizler et al. (1997).
Open with DEXTER