Astronomy & Astrophysics

All Figures

$\begin{figure} \par\includegraphics[width=15cm,clip]{2229f01.eps} \end{figure}$ Figure 1: Test of the adopted procedure: comparison of $T_{\rm eff}$ , $\log g$ , and $V\!\sin i$ parameters obtained by the fitting procedure with the model parameters of GRIDA.
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In the text

$\begin{figure} \par\includegraphics[width=14cm,clip]{2229f02.eps} \end{figure}$ Figure 2: Apparent effective temperature and surface gravity as a function of $V\!\sin i$ for different pnrc ( $T_{\rm eff}^0$ , $\log g_0$ ) values and rotation rates $\Omega /\Omega _{\rm {c}}$ .
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In the text

$\begin{figure} \par\includegraphics[width=12.5cm,clip]{2229f03a.eps}\par\vspace*{3mm} \includegraphics[width=12.5cm,clip]{2229f03b.eps} \end{figure}$ Figure 3: Upper panel: corrections $\Delta$ $T_{\rm eff}$ to add to the apparent effective temperature ( $T_{\rm eff}^{\rm app.}$ ) for different $\Omega /\Omega _{\rm {c}}$ , $V\!\sin i_{\rm ~\!app.}$ , and $\log g_{\rm app.}$ . Lower panel: corrections $\Delta$ $\log~g$ to add to the apparent surface gravity for different $\Omega /\Omega _{\rm {c}}$ , apparent $V\!\sin i$ , and apparent $T_{\rm eff}$ .
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In the text

$\begin{figure} \par\includegraphics[width=6.5cm,clip]{2229f04.eps} \end{figure}$ Figure 4: Equivalent widths of the He I 4481 and Mg II 4481 spectral lines against effective temperature for different $\log~g$ values. Computations were made assuming plane-parallel model atmospheres.
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In the text

$\begin{figure} \par\includegraphics[width=6.4cm,clip]{2229f05.eps} \end{figure}$ Figure 5: Apparent $V\!\sin i$ derived using the Fourier Transform technique against the true $V\!\sin i$ considering individually the He I 4471 line (panel a)) and Mg II 4481 spectral line (panel b)). Computations are made assuming $\Omega /\Omega _{\rm {c}}$ = 0.99.
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In the text

$\begin{figure} \par\includegraphics[width=6.6cm,clip]{2229f06.eps} {\center } \end{figure}$ Figure 6: Comparison between true and apparent $V\!\sin i$ in fast-rotating stars assuming $\log g_{\rm app.}$ = 4. The fitted regions correspond to CASE A of Table 3.
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In the text

$\begin{figure} \par\includegraphics[width=8.1cm,clip]{2229f07.eps} \end{figure}$ Figure 7: Apparent and true $V\!\sin i$ values at $T_{\rm eff}^0$ = 20 000 K, $\log g_0$ = 4.0, and for different values of $\sin~i$ (full-line curves) and of $\Omega /\Omega _{\rm {c}}$ (dotted curves).
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In the text

$\begin{figure} \par\includegraphics[width=6cm,clip]{2229f08.eps} \end{figure}$ Figure 8: $V\!\sin i$ lowering ( $\delta\!V\!\sin i$ ) as a function of the true $V\!\sin i$ fordifferent true effective temperature and true $\log~g$ values.
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In the text

$\begin{figure} \par\includegraphics[width=12.2cm,clip]{2229f09a.eps}\par\vspace*{3mm} \includegraphics[width=12.2cm,clip]{2229f09b.eps} \end{figure}$ Figure 9: Comparison between spectra computed using pnrc (full line) and apparent parameters (crosses). Pnrc spectra were computed for $T_{\rm eff}^0$ = 20 000 K, $\log g_0$ = 4.0, and $\Omega /\Omega _{\rm {c}}$ = 0.99. Three different inclination angles were considered. The values of the apparent parameters for each case are given in Table 7.
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In the text

$\begin{figure} \par\includegraphics[width=14.5cm,clip]{2229f10a.eps}\par\vspace*{2mm} \includegraphics[width=14.5cm,clip]{2229f10b.eps} \end{figure}$ Figure 10: Comparison between spectra computed using pnrc (full line) and apparent parameters (crosses). Pnrc spectra were computed for $T_{\rm eff}^0$ = 20 000 K, $\log g_0$ = 4.0, and $\Omega /\Omega _{\rm {c}}$ = 0.99. Three different inclination angles were considered. Apparent values for each case are given in Table 7.
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In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{2229f11.eps} \end{figure}$ Figure 11: Abundance overestimation in dex due to stellar flattening and gravitational darkening observed for different values of $\Omega /\Omega _{\rm {c}}$ and $V\!\sin i_{\rm ~\!app.}$ equal to 150 km s^-1 (open circles) and 200 km s^-1 (filled circles). Adopted fundamental parameters are listed in Table 6. Spectral lines used in the abundance estimate are noted in each figure.
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In the text

$\begin{figure} \par\includegraphics[width=6.4cm,clip]{2229f12.eps} \end{figure}$ Figure 12: Comparison between spectra computed using pnrc (full line) and apparent parameters (crosses). Pnrc spectra were computed for $T_{\rm eff}^0$ = 20 000 K, $\log g_0$ = 4.0, and $\Omega /\Omega _{\rm {c}}$ = 0.99. Three different inclination angles were considered. Apparent values for each case are given in Table 7.
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In the text

$\begin{figure} \par\includegraphics[width=7cm,angle=0,clip=]{2229f13.eps} \end{figure}$ Figure 13: Comparison between He I $\lambda$ 4471 line profiles computed with BRUCE (full line, Townsend et al. 2004) and with FASTROT (crosses). Adopted input parameters in FASTROT are: $T_{\rm eff}^0$ = 20 000 K, $\log g_0$ = 4.0, $\Omega /\Omega _{\rm {c}}$ = 0.99, and $V\!\sin i$ = 463 km s^-1 (i.e.: polar temperature = 22 300 K and polar radius = 4.03 $R_{\odot }$ ). Adopted input parameters in BRUCE are: polar temperature = 22 300 K, polar radius = 4.03 $R_{\odot }$ , inclination angle = 90 $^{\rm {o}}$ , and equatorial velocity = 463 km s^-1.
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In the text

$\begin{figure} \par\includegraphics[width=15cm,clip]{2229f01.eps} \end{figure}$	Figure 1: Test of the adopted procedure: comparison of $T_{\rm eff}$ , $\log g$ , and $V\!\sin i$ parameters obtained by the fitting procedure with the model parameters of GRIDA.
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$\begin{figure} \par\includegraphics[width=14cm,clip]{2229f02.eps} \end{figure}$	Figure 2: Apparent effective temperature and surface gravity as a function of $V\!\sin i$ for different pnrc ( $T_{\rm eff}^0$ , $\log g_0$ ) values and rotation rates $\Omega /\Omega _{\rm {c}}$ .
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$\begin{figure} \par\includegraphics[width=6.5cm,clip]{2229f04.eps} \end{figure}$	Figure 4: Equivalent widths of the He I 4481 and Mg II 4481 spectral lines against effective temperature for different $\log~g$ values. Computations were made assuming plane-parallel model atmospheres.
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$\begin{figure} \par\includegraphics[width=6.4cm,clip]{2229f05.eps} \end{figure}$	Figure 5: Apparent $V\!\sin i$ derived using the Fourier Transform technique against the true $V\!\sin i$ considering individually the He I 4471 line (panel a)) and Mg II 4481 spectral line (panel b)). Computations are made assuming $\Omega /\Omega _{\rm {c}}$ = 0.99.
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$\begin{figure} \par\includegraphics[width=6.6cm,clip]{2229f06.eps} {\center } \end{figure}$	Figure 6: Comparison between true and apparent $V\!\sin i$ in fast-rotating stars assuming $\log g_{\rm app.}$ = 4. The fitted regions correspond to CASE A of Table 3.
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$\begin{figure} \par\includegraphics[width=8.1cm,clip]{2229f07.eps} \end{figure}$	Figure 7: Apparent and true $V\!\sin i$ values at $T_{\rm eff}^0$ = 20 000 K, $\log g_0$ = 4.0, and for different values of $\sin~i$ (full-line curves) and of $\Omega /\Omega _{\rm {c}}$ (dotted curves).
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$\begin{figure} \par\includegraphics[width=6cm,clip]{2229f08.eps} \end{figure}$	Figure 8: $V\!\sin i$ lowering ( $\delta\!V\!\sin i$ ) as a function of the true $V\!\sin i$ fordifferent true effective temperature and true $\log~g$ values.
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$\begin{figure} \par\includegraphics[width=12.2cm,clip]{2229f09a.eps}\par\vspace*{3mm} \includegraphics[width=12.2cm,clip]{2229f09b.eps} \end{figure}$	Figure 9: Comparison between spectra computed using pnrc (full line) and apparent parameters (crosses). Pnrc spectra were computed for $T_{\rm eff}^0$ = 20 000 K, $\log g_0$ = 4.0, and $\Omega /\Omega _{\rm {c}}$ = 0.99. Three different inclination angles were considered. The values of the apparent parameters for each case are given in Table 7.
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$\begin{figure} \par\includegraphics[width=14.5cm,clip]{2229f10a.eps}\par\vspace*{2mm} \includegraphics[width=14.5cm,clip]{2229f10b.eps} \end{figure}$	Figure 10: Comparison between spectra computed using pnrc (full line) and apparent parameters (crosses). Pnrc spectra were computed for $T_{\rm eff}^0$ = 20 000 K, $\log g_0$ = 4.0, and $\Omega /\Omega _{\rm {c}}$ = 0.99. Three different inclination angles were considered. Apparent values for each case are given in Table 7.
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$\begin{figure} \par\includegraphics[width=8cm,clip]{2229f11.eps} \end{figure}$	Figure 11: Abundance overestimation in dex due to stellar flattening and gravitational darkening observed for different values of $\Omega /\Omega _{\rm {c}}$ and $V\!\sin i_{\rm ~\!app.}$ equal to 150 km s^-1 (open circles) and 200 km s^-1 (filled circles). Adopted fundamental parameters are listed in Table 6. Spectral lines used in the abundance estimate are noted in each figure.
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$\begin{figure} \par\includegraphics[width=6.4cm,clip]{2229f12.eps} \end{figure}$	Figure 12: Comparison between spectra computed using pnrc (full line) and apparent parameters (crosses). Pnrc spectra were computed for $T_{\rm eff}^0$ = 20 000 K, $\log g_0$ = 4.0, and $\Omega /\Omega _{\rm {c}}$ = 0.99. Three different inclination angles were considered. Apparent values for each case are given in Table 7.
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