All Figures

$\begin{figure} \par\includegraphics[width=9cm,clip]{9299_000.ps} \end{figure}$ Figure 1: The 1.4 GHz radio power of the selected radio sources (dots) as a function of their estimated redshift. The dashed and dotted lines show the completeness levels at 325 and 610 MHz respectively, as derived using the median flux density level of those surveys ( $5\sigma$ , Tasse et al. 2006,2007), and assuming a spectral index $\alpha = -0.8$ .
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In the text

$\begin{figure} \par\includegraphics[width=18cm,clip]{9299_001.ps} \end{figure}$ Figure 2: Using the $1/V_{\rm max}$ comoving number density estimator, we have derived the stellar mass function for normal galaxies and for the host galaxies of radio sources in different redshift bins. For the normal galaxies, at all redshifts our estimate of the stellar mass function is in good agreement with its measurement in the GOODS surveys (Fontana et al. 2006), which suggests that the stellar masses estimates are reliable. The underestimation of the mass function at low stellar masses in the redshift bins 0.4<z<0.9 and 0.7<z<1.2 is due to incompleteness. The stellar mass function of the radio source host galaxies shows a very different, evolving shape.
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In the text

$\begin{figure} \par\includegraphics[width=18cm,clip]{9299_002.ps} \end{figure}$ Figure 3: The fraction of radio sources that are radio loud as a function of the stellar mass in a given comoving volume. These relations have been derived using the mass function estimates of the normal and radio loud galaxies presented in Fig. 2. In the lower redshift bins, our measurement of the $f_{\rm RL}-M$ relation matches its SDSS/NVSS $z\lesssim 0.3$ estimate (Best et al. 2005) both in normalisation and shape. While the fraction of high stellar mass objects $M\gtrsim 10^{11}~M_{\odot}$ stays fairly constant with redshift, the fraction of lower stellar mass objects ( $10^{10.0}~M_{\odot}<M<10^{10.5}~M_{\odot}$ ) undergoes a strong evolution.
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In the text

$\begin{figure} \par\includegraphics[width=4.4cm,clip]{9299_003.ps}\includegraphics[width=4.15cm,clip]{9299_004.ps}\end{figure}$ Figure 4: This figure shows the best fit values for the parameters C₁₁ ( left panel) and ${\alpha }$ ( right panel) in each redshift bin (see text). The low values of ${\alpha }$ in the higher redshift bins suggests that the scatter introduced by the stellar mass uncertainty cannot explain the flattening of the $f_{\rm RL}-M$ relation seen in Fig. 3.
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In the text

$\begin{figure} \par\includegraphics[width=9cm,clip]{9299_005.ps}\end{figure}$ Figure 5: The averaged $V/V_{\rm max}$ in different radio power ranges for our sample, as compared to the estimates of Clewley & Jarvis (2004).
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In the text

$\begin{figure} \par\includegraphics[width=9cm,clip]{9299_006.ps}\end{figure}$ Figure 6: The averaged $V/V_{\rm max}$ in different stellar mass bins, for the normal galaxies, and for the radio source host galaxies.
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In the text

$\begin{figure} \par\mbox{\includegraphics[width=8.8cm,clip]{9299_007.ps}\includegraphics[width=8.8cm,clip]{9299_008.ps} } \end{figure}$ Figure 7: The left panel shows the infrared excess $\Delta _{\rm IR}$ at 3.6 $\mu$ m for the radio source host galaxies and for the normal galaxies. In the right panel, we compare the infrared excess of individual radio source host galaxies with normal galaxies that are in the same mass and redshift range.
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In the text

$\begin{figure} \par\mbox{\includegraphics[width=0.49\textwidth,clip]{9299_010.ps... ..._012.ps}\includegraphics[width=0.49\textwidth,clip]{9299_013.ps} }\end{figure}$ Figure 8: Overdensity estimator based on the individual photometric redshift probability functions. Top left panel shows a given region of the CFHTLS field in which we have computed the overdensity parameter at different scales for the objects brighter than i=23. The other panels show the overdensity for each object on 450, 250 and 75 kpc scales, following the color code of top right panel. The clustering at the different scales is different. The galaxy cluster that appears visually obvious in the i-band image is detected with a 450 kpc scale giving many galaxies an overdensity parameter $\rho _{450}\gtrsim 5$ . Decreasing the overdensity scale enhances small groups of galaxies or even galaxy mergers.
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In the text

$\begin{figure} \par\mbox{\includegraphics[width=8cm,clip]{9299_014.ps}\includegraphics[width=8cm,clip]{9299_015.ps} } \end{figure}$ Figure 9: Left panel: the difference in overdensity parameter $\Delta \rho$ between the radio source host galaxies, and the normal galaxies, as a function of the stellar mass. Because these two populations are significantly different in terms of redshift and magnitude distribution notably, we compare the overdensity of each radio source to the overdensity around normal galaxies in the same mass and redshift bin. This quantity is plotted for different input scales. However, the overdensity estimates on a given scale may depend on the overdensity estimate on another scale. In order to address that issue, in the right panel we compute the overdensity differences $\Delta \rho$ on small and large scale for galaxies situated in similar large and small scale environments respectively (see discussion in the text). The environmental dichotomy remains observed.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{9299_018.ps} \end{figure}$ Figure 10: The comparison between our estimate of the bolometric luminosity ( $L_{\rm X}$ (zphots)) with the bolometric luminosity $L_{\rm X}$ (zspec) as deduced using spectroscopic redshift and X-ray spectral fits. The two estimates are in reasonable agreement.
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In the text

$\begin{figure} \par\mbox{\includegraphics[width=8.8cm,clip]{9299_019.ps}\include... ...ip]{9299_021.ps}\includegraphics[width=8.8cm,clip]{9299_022.ps} } \end{figure}$ Figure 11: Top left panel: the overdensity parameter for the galaxies aligned with X-ray cluster emission and field galaxies in the same redshift ranges. The overdensity parameter appears to be quite efficient. Top right to bottom right: the difference in overdensity parameter between the galaxies aligned with X-ray cluster emission and the field galaxies for different X-ray luminosities. In each panel, the estimated redshift distribution of the X-ray clusters is indicated (full line), and compared to the redshift distribution of the radio source host galaxies (dashed line). Although our overdensity parameter is biased by redshift, it seems that the increase of the halo mass leads to a higher overdensity parameter estimate. Comparing this with Fig. 9, it seems that massive radio sources lie in rather small clusters on average.
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In the text

$\begin{figure} \par\includegraphics[width=9cm,clip]{9299_000.ps} \end{figure}$	Figure 1: The 1.4 GHz radio power of the selected radio sources (dots) as a function of their estimated redshift. The dashed and dotted lines show the completeness levels at 325 and 610 MHz respectively, as derived using the median flux density level of those surveys ( $5\sigma$ , Tasse et al. 2006,2007), and assuming a spectral index $\alpha = -0.8$ .
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$\begin{figure} \par\includegraphics[width=4.4cm,clip]{9299_003.ps}\includegraphics[width=4.15cm,clip]{9299_004.ps}\end{figure}$	Figure 4: This figure shows the best fit values for the parameters C₁₁ ( left panel) and ${\alpha }$ ( right panel) in each redshift bin (see text). The low values of ${\alpha }$ in the higher redshift bins suggests that the scatter introduced by the stellar mass uncertainty cannot explain the flattening of the $f_{\rm RL}-M$ relation seen in Fig. 3.
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$\begin{figure} \par\includegraphics[width=9cm,clip]{9299_005.ps}\end{figure}$	Figure 5: The averaged $V/V_{\rm max}$ in different radio power ranges for our sample, as compared to the estimates of Clewley & Jarvis (2004).
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$\begin{figure} \par\includegraphics[width=9cm,clip]{9299_006.ps}\end{figure}$	Figure 6: The averaged $V/V_{\rm max}$ in different stellar mass bins, for the normal galaxies, and for the radio source host galaxies.
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$\begin{figure} \par\mbox{\includegraphics[width=8.8cm,clip]{9299_007.ps}\includegraphics[width=8.8cm,clip]{9299_008.ps} } \end{figure}$	Figure 7: The left panel shows the infrared excess $\Delta _{\rm IR}$ at 3.6 $\mu$ m for the radio source host galaxies and for the normal galaxies. In the right panel, we compare the infrared excess of individual radio source host galaxies with normal galaxies that are in the same mass and redshift range.
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$\begin{figure} \par\includegraphics[width=8.8cm,clip]{9299_018.ps} \end{figure}$	Figure 10: The comparison between our estimate of the bolometric luminosity ( $L_{\rm X}$ (zphots)) with the bolometric luminosity $L_{\rm X}$ (zspec) as deduced using spectroscopic redshift and X-ray spectral fits. The two estimates are in reasonable agreement.
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