All Figures

$\begin{figure} \par\includegraphics[width=7.4cm,clip]{2235Fig_1.ps} \end{figure}$ Figure 1: Contours of the mean of STAR#3 and STAR#4 deconvolved images. The contour levels are linearly spaced for the double square root of the image I^1/4. The last contour is equivalent to 25% of the maximum of I^1/4, i.e. 0.4% of the maximum of I. The three last contours are the most susceptible to reconstruction artifacts. The North is up and the east to the left.
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In the text

$\begin{figure} \par\includegraphics[width=6.7cm,clip]{2235Fig_2.ps}\par\end{figure}$ Figure 2: Contours of the reconstructed L image from the speckle observations at the ESO 3.6 m telescope on La Silla (courtesy of Starck et al.). The contour levels are linearly spaced for the square root of the image I^1/2.
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In the text

$\begin{figure} \par\includegraphics[width=8.6cm,clip]{2235Fig_3.ps} \end{figure}$ Figure 3: Calibrated spectrum from MIDI (solid line) corresponding to the mean flux from UT1 and UT3. The flux is almost 300% higher than the flux observed by ISO, shown with a dotted line. The ISO data were recorded during a minimum of the lightcurve.
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In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{2235Fig_4.ps} \end{figure}$ Figure 4: FWHM of the star spectrum from UT1 (solid lines) throughout the wavelength range compared to FWHM of the calibrator spectrum of HD 168454 (dotted lines). There are two lines per target because the MIDI beam splitter is inserted and the light falls onto two different regions of the detector.
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In the text

$\begin{figure} \par\includegraphics[width=7.4cm,clip]{2235Fig_5.ps} \end{figure}$ Figure 5: Mean of FWHM curves of the star deconvolved spectra from UT3 (solid lines) and the individual deconvolution using different calibrators (dotted lines). The errors bars of the figure (spaced by 0.5 $\mu$ m intervals) represent only the scatter of the measurements.
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In the text

$\begin{figure} \par\includegraphics[width=7.9cm,clip]{2235Fig_6.ps} \end{figure}$ Figure 6: Comparison between the ISO spectra (SWS + LWS) and a MODUST model using the JU96 parameters but with slightly reduced luminosity of the central star. Other differences are the use of CDE theory and inclusion of metallic iron. The crystalline features present in the ISO-SWS observations are not included in the model since they have little effect on the model structure (Kemper et al. 2002).
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In the text

$\begin{figure} \par\includegraphics[width=7.6cm,clip]{2235Fig_7.ps} \end{figure}$ Figure 7: Comparison between the MIDI spectrum (original: solid line, dereddened for IS extinction: dashed line) and the spectrum resulting from our ISO-tuned model but with increased central star luminosity (diamonds).
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In the text

$\begin{figure} \par\includegraphics[width=7.3cm,clip]{2235Fig_8.ps} \end{figure}$ Figure 8: A comparison between the FWHMs of the intensity profiles coming from the ISO-tuned model with a more luminous central star and the MIDI FWHMs. The predicted variation of diameter with wavelength is much larger than the one observed. Mainly the size at minimum optical thickness of the shell (at 8.5 and 13.5 $\mu$ m) does not agree.
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In the text

$\begin{figure} \par\includegraphics[width=7.5cm,clip]{2235Fig_9.ps} \end{figure}$ Figure 9: Normalized intensity profiles for our model at maximum luminosity. In the wings of the 9.7 $\mu$ m profile (at 8.5 and 13.5 $\mu$ m), the shell optical thickness is only about 2 and thus the central star is visible. At 10.5 $\mu$ m, the shell reaches an optical thickness of more than 10, resulting in the Gaussian intensity profile.
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In the text

$\begin{figure} \par\includegraphics[width=7.4cm,clip]{2235Fig_10.ps} \end{figure}$ Figure 10: Normalized intensity profiles for our model at maximum luminosity with an increased inner radius. For such intensity profiles, the inner radius determines the observed size of the object at wavelengths of low opacity.
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In the text

$\begin{figure} \par\includegraphics[width=7.3cm,clip]{2235Fig_11.ps} \end{figure}$ Figure 11: Angular diameter fro our model compared to the MIDI data. The large observed radius at the red and blue sides of the profile can be simulated by moving the inner radius of the model far out, to about $20~ R_{\star}$ .
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In the text

$\begin{figure} \par\includegraphics[width=7.4cm,clip]{2235Fig_1.ps} \end{figure}$	Figure 1: Contours of the mean of STAR#3 and STAR#4 deconvolved images. The contour levels are linearly spaced for the double square root of the image I^1/4. The last contour is equivalent to 25% of the maximum of I^1/4, i.e. 0.4% of the maximum of I. The three last contours are the most susceptible to reconstruction artifacts. The North is up and the east to the left.
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$\begin{figure} \par\includegraphics[width=6.7cm,clip]{2235Fig_2.ps}\par\end{figure}$	Figure 2: Contours of the reconstructed L image from the speckle observations at the ESO 3.6 m telescope on La Silla (courtesy of Starck et al.). The contour levels are linearly spaced for the square root of the image I^1/2.
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$\begin{figure} \par\includegraphics[width=8.6cm,clip]{2235Fig_3.ps} \end{figure}$	Figure 3: Calibrated spectrum from MIDI (solid line) corresponding to the mean flux from UT1 and UT3. The flux is almost 300% higher than the flux observed by ISO, shown with a dotted line. The ISO data were recorded during a minimum of the lightcurve.
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$\begin{figure} \par\includegraphics[width=8cm,clip]{2235Fig_4.ps} \end{figure}$	Figure 4: FWHM of the star spectrum from UT1 (solid lines) throughout the wavelength range compared to FWHM of the calibrator spectrum of HD 168454 (dotted lines). There are two lines per target because the MIDI beam splitter is inserted and the light falls onto two different regions of the detector.
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$\begin{figure} \par\includegraphics[width=7.4cm,clip]{2235Fig_5.ps} \end{figure}$	Figure 5: Mean of FWHM curves of the star deconvolved spectra from UT3 (solid lines) and the individual deconvolution using different calibrators (dotted lines). The errors bars of the figure (spaced by 0.5 $\mu$ m intervals) represent only the scatter of the measurements.
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$\begin{figure} \par\includegraphics[width=7.6cm,clip]{2235Fig_7.ps} \end{figure}$	Figure 7: Comparison between the MIDI spectrum (original: solid line, dereddened for IS extinction: dashed line) and the spectrum resulting from our ISO-tuned model but with increased central star luminosity (diamonds).
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$\begin{figure} \par\includegraphics[width=7.3cm,clip]{2235Fig_8.ps} \end{figure}$	Figure 8: A comparison between the FWHMs of the intensity profiles coming from the ISO-tuned model with a more luminous central star and the MIDI FWHMs. The predicted variation of diameter with wavelength is much larger than the one observed. Mainly the size at minimum optical thickness of the shell (at 8.5 and 13.5 $\mu$ m) does not agree.
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$\begin{figure} \par\includegraphics[width=7.5cm,clip]{2235Fig_9.ps} \end{figure}$	Figure 9: Normalized intensity profiles for our model at maximum luminosity. In the wings of the 9.7 $\mu$ m profile (at 8.5 and 13.5 $\mu$ m), the shell optical thickness is only about 2 and thus the central star is visible. At 10.5 $\mu$ m, the shell reaches an optical thickness of more than 10, resulting in the Gaussian intensity profile.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=7.4cm,clip]{2235Fig_10.ps} \end{figure}$	Figure 10: Normalized intensity profiles for our model at maximum luminosity with an increased inner radius. For such intensity profiles, the inner radius determines the observed size of the object at wavelengths of low opacity.
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$\begin{figure} \par\includegraphics[width=7.3cm,clip]{2235Fig_11.ps} \end{figure}$	Figure 11: Angular diameter fro our model compared to the MIDI data. The large observed radius at the red and blue sides of the profile can be simulated by moving the inner radius of the model far out, to about $20~ R_{\star}$ .
Open with DEXTER