All Figures

$\begin{figure} \par\begin{tabular}{ll} & \\ (a) & (b) \\ \psfig{file=5392f1... ...=8.5cm} & \psfig{file=5392f1b.ps,angle=90,width=8.5cm}\end{tabular}\end{figure}$ Figure 1: Diagnostic plots used for the initial estimation of atmospheric parameters assuming a microturbulence of 5 $\mbox{km~s}^{-1}$ : ( left) the ratio of the equivalent width of the He I line at 4026 Å to the mean of the hydrogen H $\gamma$ and H $\delta$ equivalent widths; the ratio is plotted as a function of effective temperature ( $T_{\rm eff}$ ) for three logarithmic surface gravities: ( right) the mean equivalent widths of the H $\gamma$ and H $\delta$ lines on a logarithmic scale plotted as a function of effective temperature ( $T_{\rm eff}$ ) for five logarithmic surface gravities.
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In the text

$\begin{figure} \par\includegraphics[angle=90,width=6.8cm]{5392f2.ps} \end{figure}$ Figure 2: An example of the chi-square minimization procedure used to estimate the projected rotational velocity for the star 4755-030.
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In the text

$\begin{figure} \par\includegraphics[angle=270,width=6cm]{5392f3a.ps}\par\vspace*{2mm} \includegraphics[angle=270,width=6cm]{5392f3b.ps} \end{figure}$ Figure 3: Observed and rotationally broadened theoretical helium line profiles. 4755-033 ( upper panel) and 4755-030 ( lower panel) have estimated values of v sin i of 75 and 330 $\mbox{km~s}^{-1}$ , respectively.
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In the text

$\begin{figure} \par\includegraphics[angle=90,width=7.5cm]{5392f4.ps}\end{figure}$ Figure 4: Initial estimates of atmospheric parameters for targets in NGC 3293, deduced from the hydrogen and helium equivalent widths.
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In the text

$\begin{figure} \par\includegraphics[angle=90,width=7.5cm]{5392f5.ps} \end{figure}$ Figure 5: The procedure to correct the atmospheric parameter estimates for stellar rotation is illustrated for a value of v sin i of 300 km s^-1. Plus sign (+) mark the atmospheric parameters deduced when the effects of rotation are included. Diamonds symbols ( $\diamond$ ) connected by a line, represent the original atmospheric parameters, which are designated by the adjacent pairs of numbers (note $T_{\rm eff}$ is in $\times$ 1000 K). The correction factors are given in parenthesis.
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In the text

$\begin{figure} \par\includegraphics[width=8.5cm,clip]{5392f6a.eps}\par\vspace*{2... ...s}\par\vspace*{2mm} \includegraphics[width=8.5cm,clip]{5392f6c.eps} \end{figure}$ Figure 6: Hertzsprung-Russell diagrams for the three clusters, together with evolutionary tracks and isochrones taken from the Geneva database. Stars with estimated gravities of less than 3.9 dex are shown as open circles with higher gravity stars represented by closed circles.
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In the text

$\begin{figure} \par\includegraphics[width=6cm,clip]{5392f7a.eps}\par\vspace*{2mm... ...eps}\par\vspace*{2mm} \includegraphics[width=6cm,clip]{5392f7c.eps} \end{figure}$ Figure 7: Present day mass functions for the three clusters.
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In the text

$\begin{figure} \par\includegraphics[angle=270,width=6cm,clip]{5392f8a.ps}\par\vs... ...vspace*{2mm} \includegraphics[angle=270,width=6cm,clip]{5392f8c.ps} \end{figure}$ Figure 8: Histograms of projected rotational velocities for each of the three cluster.
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In the text

$\begin{figure} \par\includegraphics[angle=270,width=15cm]{5392f9.eps} \end{figure}$ Figure 9: Cumulative probability function for all targets in our two older clusters and in h and $\chi$ Persei and for those in the different classes as specified by Strom et al. (2005). Group 1 - relatively unevolved stars with an effective temperature, $T_{\rm eff}$ < 17 000; Group 2 - stars with 17 000 $\leq$ $T_{\rm eff}$ < 21 000; Group 3 - stars that have evolved significantly from the main sequence, $T_{\rm eff}$ $\geq$ 21 000. The solid lines are for field stars, the dotted lines are for the h and $\chi$ Persei sample of Strom et al. (2005) and the dot-dash lines are our combined sample for the clusters NGC 3293 and NGC 4755.
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In the text

$\begin{figure} \par\includegraphics[width=8.5cm,clip]{5392f10.eps} \end{figure}$ Figure 10: Hertzsprung-Russell diagrams for the h and $\chi$ Persei cluster, together with evolutionary tracks and isochrones taken from the Geneva database.
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In the text

$\begin{figure} \par\includegraphics[angle=270,width=6.5cm,clip]{5392f11a.eps}\pa... ...ce*{2mm} \includegraphics[angle=270,width=6.5cm,clip]{5392f11b.eps} \end{figure}$ Figure 11: The histogram of the observed projected rotational velocities for targets in the clusters NGC 3293 and NGC 4755 is compared with models assuming an intrinsic rotational velocity distribution of a delta-function a) and a uniform distribution b). The histogram data includes only stars in the mass range 3-15 $M_\odot$ i.e. the evolved objects have been removed. In panel a) all stars have been assumed to rotate at velocities of 350 $\mbox{km~s}^{-1}$ (solid curve) and 250 $\mbox{km~s}^{-1}$ (dashed curve). In panel b) continuous distributions of velocities between zero and a maximum of 350 $\mbox{km~s}^{-1}$ (solid curve) and 250 $\mbox{km~s}^{-1}$ (dashed curve) are assumed. It is clear that neither rotational velocity distribution provides convincing agreement with the observed velocity histograms.
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In the text

$\begin{figure} \par\includegraphics[width=7cm,clip]{5392f12a.eps}\par\vspace*{2mm} \includegraphics[width=7cm,clip]{5392f12b.eps} \end{figure}$ Figure 12: Upper panel: the histogram of observed projected rotational velocities for targets in the clusters NGC 3293 and NGC 4755 is compared with the model assuming a Gaussian distribution of rotational velocities. The Gaussian has a maximum at a rotational velocity 250 $\mbox{km~s}^{-1}$ and a $\sigma =110$ $\mbox{km~s}^{-1}$ . The histogram data includes only stars in the mass range 3-15 $M_\odot$ i.e. the evolved objects have been removed. Lower Panel: the NGC 6611 stars, with a Gaussian distribution with a maximum at 175 $\mbox{km~s}^{-1}$ and a $\sigma =100$ $\mbox{km~s}^{-1}$ .
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In the text

$\begin{figure} \par\includegraphics[width=7.8cm,clip]{5392f13a.eps}\par\vspace*{... ...}\par\vspace*{2mm} \includegraphics[width=7.8cm,clip]{5392f13c.eps} \end{figure}$ Figure 13: Hertzsprung-Russell diagrams for the three clusters together with rotating stellar evolutionary models from the Geneva group. The symbols are as in Fig. 6, and all the models have an initial equatorial rotational velocity of 300 $\mbox{km~s}^{-1}$ . The tracks for the 25-60 $M_\odot$ models have been truncated before the bluewards evolution towards the WR phase, to aid clarity.
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In the text

$\begin{figure} \par\includegraphics[width=16.8cm,clip]{5392fc6.eps} \end{figure}$ Figure A.1: VLT-FLAMES targets (open circles) and FEROS targets (open squares) in the NGC 6611 field.

In the text

$\begin{figure} \par\includegraphics[width=15cm,clip]{5392fc3c.eps} \end{figure}$ Figure A.2: VLT-FLAMES targets (open circles) and FEROS targets (open squares) in the inner 7' of the NGC 3293 field.

In the text

$\begin{figure} \par\includegraphics[width=16.8cm,clip]{5392fc3.eps} \end{figure}$ Figure A.3: VLT-FLAMES targets (open circles) and FEROS targets (open squares) in the NGC 3293 field. Most of the objects observed in the inner region are shown separately in Fig. A.2.

In the text

$\begin{figure} \par\includegraphics[width=15cm,clip]{5392fc4c.eps} \end{figure}$ Figure A.4: VLT-FLAMES targets (open circles) and FEROS targets (open squares) in the inner 7' of the NGC 4755 field.

In the text

$\begin{figure} \par\includegraphics[width=16.8cm,clip]{5392fc4.eps}\end{figure}$ Figure A.5: VLT-FLAMES targets (open circles) and FEROS targets (open squares) in the NGC 4755 field. Most of the objects observed in the inner region are shown separately in Fig. A.4.

In the text

$\begin{figure} \par\includegraphics[angle=90,width=6.8cm]{5392f2.ps} \end{figure}$	Figure 2: An example of the chi-square minimization procedure used to estimate the projected rotational velocity for the star 4755-030.
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$\begin{figure} \par\includegraphics[angle=270,width=6cm]{5392f3a.ps}\par\vspace*{2mm} \includegraphics[angle=270,width=6cm]{5392f3b.ps} \end{figure}$	Figure 3: Observed and rotationally broadened theoretical helium line profiles. 4755-033 ( upper panel) and 4755-030 ( lower panel) have estimated values of v sin i of 75 and 330 $\mbox{km~s}^{-1}$ , respectively.
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$\begin{figure} \par\includegraphics[angle=90,width=7.5cm]{5392f4.ps}\end{figure}$	Figure 4: Initial estimates of atmospheric parameters for targets in NGC 3293, deduced from the hydrogen and helium equivalent widths.
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$\begin{figure} \par\includegraphics[width=8.5cm,clip]{5392f6a.eps}\par\vspace{2... ...s}\par\vspace{2mm} \includegraphics[width=8.5cm,clip]{5392f6c.eps} \end{figure}$	Figure 6: Hertzsprung-Russell diagrams for the three clusters, together with evolutionary tracks and isochrones taken from the Geneva database. Stars with estimated gravities of less than 3.9 dex are shown as open circles with higher gravity stars represented by closed circles.
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$\begin{figure} \par\includegraphics[width=6cm,clip]{5392f7a.eps}\par\vspace{2mm... ...eps}\par\vspace{2mm} \includegraphics[width=6cm,clip]{5392f7c.eps} \end{figure}$	Figure 7: Present day mass functions for the three clusters.
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$\begin{figure} \par\includegraphics[angle=270,width=6cm,clip]{5392f8a.ps}\par\vs... ...vspace*{2mm} \includegraphics[angle=270,width=6cm,clip]{5392f8c.ps} \end{figure}$	Figure 8: Histograms of projected rotational velocities for each of the three cluster.
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$\begin{figure} \par\includegraphics[width=8.5cm,clip]{5392f10.eps} \end{figure}$	Figure 10: Hertzsprung-Russell diagrams for the h and $\chi$ Persei cluster, together with evolutionary tracks and isochrones taken from the Geneva database.
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$\begin{figure} \par\includegraphics[width=7.8cm,clip]{5392f13a.eps}\par\vspace{... ...}\par\vspace{2mm} \includegraphics[width=7.8cm,clip]{5392f13c.eps} \end{figure}$	Figure 13: Hertzsprung-Russell diagrams for the three clusters together with rotating stellar evolutionary models from the Geneva group. The symbols are as in Fig. 6, and all the models have an initial equatorial rotational velocity of 300 $\mbox{km~s}^{-1}$ . The tracks for the 25-60 $M_\odot$ models have been truncated before the bluewards evolution towards the WR phase, to aid clarity.
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