$\begin{figure} \par\includegraphics[width=8.8cm,clip]{0786fig1.ps} \end{figure}$ Figure 1: Optical V filter image of the field around SAX J2103.5+4545, with the X-ray position uncertainty circles from the WFC onboard BeppoSAX (99% confidence level) and ISGRI and JEM-X onboard INTEGRAL (90% confidence level). The coordinates of the proposed optical counterpart are $\rm RA=21$ :03:35.7 $\rm Dec=+45$ :45:04 (Eq. 2000).
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{0786fig2.ps} \end{figure}$ Figure 2: Colour-colour diagram of the field around SAX J2103.5+4545. The star symbol marks the position of the proposed optical counterpart. Filled-circles represent strong H $\alpha$ emitters, while open circles correspond to field stars.
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In the text

$\begin{figure} \par\includegraphics[width=16cm,height=9cm,clip]{0786fig3.ps} \end{figure}$ Figure 3: Blue spectrum showing the lines used for spectral classification. The spectrum was taken from the WHT on August 17, 2003. The He I lines marked are $\lambda$ 4026, $\lambda$ 4121, $\lambda$ 4144, $\lambda$ 4387, $\lambda$ 4471, $\lambda$ 4713. Also shown is the insterstellar line Ca II $\lambda$ 3934.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{0786fig5.ps} \end{figure}$ Figure 5: Blue- and red-end spectra of the optical companion of SAX J2103.5+4545. We have indicated the diffuse interstellar bands used for the derivation of the reddening and the Helium lines $\lambda$ 5875, $\lambda$ 6678, $\lambda$ 7065. The Balmer series up to H₁₃ can be seen. The spectra were taken from the WHT on September 14, 2003.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{0786fig6.ps} \end{figure}$ Figure 6: $P_{\rm spin}-P_{\rm orb}$ diagram. The star symbol marks the position of SAX J2103.5+4545. Circles represent Be/X-ray binaries, triangles identify wind-fed supergiants and squares refer to disc-fed (Roche-lobe filling) systems.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{0786fig1.ps} \end{figure}$	Figure 1: Optical V filter image of the field around SAX J2103.5+4545, with the X-ray position uncertainty circles from the WFC onboard BeppoSAX (99% confidence level) and ISGRI and JEM-X onboard INTEGRAL (90% confidence level). The coordinates of the proposed optical counterpart are $\rm RA=21$ :03:35.7 $\rm Dec=+45$ :45:04 (Eq. 2000).
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{0786fig2.ps} \end{figure}$	Figure 2: Colour-colour diagram of the field around SAX J2103.5+4545. The star symbol marks the position of the proposed optical counterpart. Filled-circles represent strong H $\alpha$ emitters, while open circles correspond to field stars.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=16cm,height=9cm,clip]{0786fig3.ps} \end{figure}$	Figure 3: Blue spectrum showing the lines used for spectral classification. The spectrum was taken from the WHT on August 17, 2003. The He I lines marked are $\lambda$ 4026, $\lambda$ 4121, $\lambda$ 4144, $\lambda$ 4387, $\lambda$ 4471, $\lambda$ 4713. Also shown is the insterstellar line Ca II $\lambda$ 3934.
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$\begin{figure} \par\includegraphics[width=8.8cm,clip]{0786fig4.eps} \end{figure}$	Figure 4: Evolution of the H $\alpha$ line.
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$\begin{figure} \par\includegraphics[width=8.8cm,clip]{0786fig5.ps} \end{figure}$	Figure 5: Blue- and red-end spectra of the optical companion of SAX J2103.5+4545. We have indicated the diffuse interstellar bands used for the derivation of the reddening and the Helium lines $\lambda$ 5875, $\lambda$ 6678, $\lambda$ 7065. The Balmer series up to H₁₃ can be seen. The spectra were taken from the WHT on September 14, 2003.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{0786fig6.ps} \end{figure}$	Figure 6: $P_{\rm spin}-P_{\rm orb}$ diagram. The star symbol marks the position of SAX J2103.5+4545. Circles represent Be/X-ray binaries, triangles identify wind-fed supergiants and squares refer to disc-fed (Roche-lobe filling) systems.
Open with DEXTER