All Figures

$\begin{figure} \par\includegraphics[width=17cm,clip=true]{2208fig1.ps} \end{figure}$ Figure 1: a) Gray-scale image showing the depth of a $2300\times 2300$ pixel J-band mosaic. The lighter regions indicate higher noise due to a smaller number of exposures or bad pixels. Each sky position is measured at least 4 times. The rightmost two frames show a typical field in J- and R-band. The black line encloses the usable region ( b) and c) respectively).
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In the text

$\begin{figure} \par\resizebox{6.2cm}{!}{\includegraphics[]{2208fig2.ps}} \end{figure}$ Figure 2: Distribution on the sky of 3 survey fields, with a field size of about ( $15\times 15$ ) arcmin². The symbols identify the detected EROs( $R-J\ge 5$ ). Fields are named by the letter G, followed by a three digit sequence number.
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In the text

$\begin{figure} \par\resizebox{6.2cm}{!}{\includegraphics[]{2208fig3.ps}} \end{figure}$ Figure 3: The R-band zero point calibration for a typical field, based on Sloan Digital Sky Survey magnitudes. After correcting the assumed zero point, our photometry agrees very well with the SDSS results (standard deviation $\le \pm 0.006$ mag).
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In the text

$\begin{figure} \par\resizebox{8.4cm}{!}{\includegraphics{2208fig4.ps}} \end{figure}$ Figure 4: The R-band detection limit is given by the magnitude at which the majority of photometric errors reach 0.1 mag.
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In the text

$\begin{figure} \includegraphics[width=14cm,clip]{2208fig5.ps} \end{figure}$ Figure 5: Colour evolution for different models representing an evolved elliptical galaxy, a dust reddened starburst and a normal spiral galaxy both in an edge-on and face-on orientation. The three panels show the evolution of R-J (panel a)), R-K (panel b)) and J-K (panel c)) colours for all 5 models described in Sect. 3.1. The horizontal dashed line shows the applied colour threshold of our EROs selection $R-J\ge 5$ , indicating that we select only ellipticals at redshift 1.4 and above with this colour criteria.
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In the text

$\begin{figure} \par\resizebox{7.2cm}{!}{\includegraphics{2208fig6.ps}} \end{figure}$ Figure 6: Differential counts (number mag^-1 deg^-2) of galaxies in the J-band compared to a collection of published data, including Saracco et al. (1999), Martini (2001), Väisänen et al. (2000) and the MUNICS survey (Drory et al. 2001). The error bars for our data represent only counting statistics.
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In the text

$\begin{figure} \par\includegraphics[width=16.3cm,clip]{2208fig7.ps} \end{figure}$ Figure 7: R-J colour distribution for all galaxies, i.e. stellarity index $\le$ 0.8 in R and J-band. Magnitude ranges are indicated in the upper left-hand corner of each panel. The data show the colour distributions without visual check (as was done for the final catalogue of extremely red objects, $R-J\ge 5$ ), i.e. objects to the left of the dashed line were not manually checked in each individual frame. The error bars indicate the Poisson uncertainties and the dot-dashed lines show the one or two Gaussians used to fit the peak position and width of the distribution reported in Table 2. The second peak is the result of assigning the limiting R magnitude to objects with no optical detection (see text for details).
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In the text

$\begin{figure} \includegraphics[width=14.4cm]{2208fig8.ps} \end{figure}$ Figure 8: Examples of EROs, with R-band detection ( leftmost three panels) and without optical detection ( rightmost two panels). The images are 40 $\hbox {$^{\prime \prime }$ }$ on a side.
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In the text

$\begin{figure} \par\rotatebox{90}{\includegraphics[height=13cm]{2208fig9.ps}} \end{figure}$ Figure 9: Colour-magnitude diagram for extremely red stellar objects (19) and galaxies (60) found in our survey. For objects without R detection, the star/galaxy classification in R is arbitrary and solely based on the SExtractor result, the dashed line marks the $R-J\ge 5$ colour threshold.
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In the text

$\begin{figure} \par\rotatebox{0}{\includegraphics[width=6.2cm]{2208fig10.ps}} \end{figure}$ Figure 10: Cumulative ERO surface density from this work, compared to the results for $R-K\ge 7$ objects from Daddi et al. (2000). The uncertainties are derived assuming only Poisson counting statistics. To convert the Daddi K-band magnitudes into J-band we use the result of the stellar population synthesis models, which found a J-K=2.25 for objects with $R-J\ge 5$ (Fig. 5).
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In the text

$\begin{figure} \par\resizebox{6.5cm}{!}{\includegraphics{2208fig11.ps}} \end{figure}$ Figure 11: Number distribution of the 60 extremely red galaxies found in 50 survey fields.
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In the text

$\begin{figure} \par\includegraphics[width=17cm,clip=true]{2208fig1.ps} \end{figure}$	Figure 1: a) Gray-scale image showing the depth of a $2300\times 2300$ pixel J-band mosaic. The lighter regions indicate higher noise due to a smaller number of exposures or bad pixels. Each sky position is measured at least 4 times. The rightmost two frames show a typical field in J- and R-band. The black line encloses the usable region ( b) and c) respectively).
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$\begin{figure} \par\resizebox{6.2cm}{!}{\includegraphics[]{2208fig2.ps}} \end{figure}$	Figure 2: Distribution on the sky of 3 survey fields, with a field size of about ( $15\times 15$ ) arcmin². The symbols identify the detected EROs( $R-J\ge 5$ ). Fields are named by the letter G, followed by a three digit sequence number.
Open with DEXTER

$\begin{figure} \par\resizebox{6.2cm}{!}{\includegraphics[]{2208fig3.ps}} \end{figure}$	Figure 3: The R-band zero point calibration for a typical field, based on Sloan Digital Sky Survey magnitudes. After correcting the assumed zero point, our photometry agrees very well with the SDSS results (standard deviation $\le \pm 0.006$ mag).
Open with DEXTER

$\begin{figure} \par\resizebox{8.4cm}{!}{\includegraphics{2208fig4.ps}} \end{figure}$	Figure 4: The R-band detection limit is given by the magnitude at which the majority of photometric errors reach 0.1 mag.
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$\begin{figure} \par\resizebox{7.2cm}{!}{\includegraphics{2208fig6.ps}} \end{figure}$	Figure 6: Differential counts (number mag^-1 deg^-2) of galaxies in the J-band compared to a collection of published data, including Saracco et al. (1999), Martini (2001), Väisänen et al. (2000) and the MUNICS survey (Drory et al. 2001). The error bars for our data represent only counting statistics.
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$\begin{figure} \includegraphics[width=14.4cm]{2208fig8.ps} \end{figure}$	Figure 8: Examples of EROs, with R-band detection ( leftmost three panels) and without optical detection ( rightmost two panels). The images are 40 $\hbox {$^{\prime \prime }$ }$ on a side.
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$\begin{figure} \par\rotatebox{90}{\includegraphics[height=13cm]{2208fig9.ps}} \end{figure}$	Figure 9: Colour-magnitude diagram for extremely red stellar objects (19) and galaxies (60) found in our survey. For objects without R detection, the star/galaxy classification in R is arbitrary and solely based on the SExtractor result, the dashed line marks the $R-J\ge 5$ colour threshold.
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$\begin{figure} \par\rotatebox{0}{\includegraphics[width=6.2cm]{2208fig10.ps}} \end{figure}$	Figure 10: Cumulative ERO surface density from this work, compared to the results for $R-K\ge 7$ objects from Daddi et al. (2000). The uncertainties are derived assuming only Poisson counting statistics. To convert the Daddi K-band magnitudes into J-band we use the result of the stellar population synthesis models, which found a J-K=2.25 for objects with $R-J\ge 5$ (Fig. 5).
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$\begin{figure} \par\resizebox{6.5cm}{!}{\includegraphics{2208fig11.ps}} \end{figure}$	Figure 11: Number distribution of the 60 extremely red galaxies found in 50 survey fields.
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