All Figures

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{H4135_F1.eps} \end{figure}$ Figure 1: Reflectivity, $\tilde{{\cal R}}$ , of the coma of comet Hale-Bopp on January 20/21, 2001, averaged over 4600 km projected nucleocentric distance both sides of the nucleus and normalized at a wavelength of 6000 Å. The signature at approximately 5600 Å is a remnant of a night sky emission line. The "blue'' and "red'' intervals as described in the text are marked.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{H4135_F2.eps} \end{figure}$ Figure 2: Spatial reddening profile for August 28/29, 2000. Filled symbols show the reddening on the "blue'' interval (4100 Å to 5400 Å), open symbols on the "red'' interval (5400 Å to 6100 Å) along the slit versus projected distance from the nucleus. Negative distances denote the sunward side, positive distances the tailward side of the nucleus.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{H4135_F3.eps} \end{figure}$ Figure 3: Mean reddening in the coma of comet Hale-Bopp, for the "blue'' wavelength interval (top panel) and the "red'' interval (lower panel). Filled and open symbols mark data derived from the sunward and tailward side of the coma.
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In the text

$\begin{figure} \par\includegraphics[width=14cm,clip]{H4135_F4.eps} \end{figure}$ Figure 4: Af $\rho$ from this work (from R-filter images and long slit spectra) and some previous publications. No corrections concerning the phase angle were applied on any of the shown data. Values from Schleicher are from observations made at Perth Observatory by Peter Birch, reductions by David Schleicher and supplied by personal communication. The dotted lines indicate the perihelion distance.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{H4135_F5.eps} \end{figure}$ Figure 5: Size dependent nucleocentric terminal dust velocities. The dust velocities calculated for grain radii $a=10~\mu$ m, $2~\mu$ m and $0.5~\mu$ m, are shown. Dust ejection velocities derived from observations are shown for comparison. The dust velocity from Fulle et al. (1998) is derived from coma modeling for a particle radius of 10 $\mu$ m. The values from Braunstein et al. (1999) and Sekanina (1996) are dust ejection velocities estimated from movements of coma structures. The triangles give projected dust velocities (thus lower limits) from different publications as derived from observations of coma features: 1: Kidger et al. (1996), 2: Sekanina (1996), 3: Tozzi et al. (1999), 4: McCarthy et al. (1999), 5: Lecacheux et al. (1997), 6: Warell et al. (1999),7: Lisse et al. (1999). The line indicates a dependency according to $v_{\rm dust} \sim r_{\rm h}^{-0.5}$ .
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{H4135_F6.eps} \end{figure}$ Figure 6: Maximum dust grain radii $a_{\rm max}$ that can be lifted from the nucleus surface of comet Hale-Bopp versus heliocentric distance. $a_{\rm max}$ is shown for different model parameters (see text): A: R_N = 30 km, f = 5%, B: R_N = 25 km, f= 19 %, C: R_N = 30 km, f = 19%, D: R_N = 35 km, f = 19%, E: R_N = 30 km, f = 50%. The filled symbols mark $a_{\rm max}$ as used for the determination of the dust production rates.
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{H4135_F7.eps} \end{figure}$ Figure 7: Dust production rates, determined with the model described in Sect. 5. Filled symbols show mass production rates (left scale), empty symbols production rates by number (right scale).
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In the text

$\begin{figure} \par\includegraphics[width=8.2cm,clip]{H4135_F8.eps} \end{figure}$ Figure 8: Dust mass production rates for different model parameters. Upper panel: R_N = 30 km and active surface fractions fof 5%, 19% and 50% of the total surface. Lower panel: active surface fraction f = 19% and R_N of 25 km, 30 km and 35 km. The values for the preferred parameters (R_N = 30 km, f = 19%) are shown (dots) and power law fits to the dust production rates calculated with the different parameters are plotted.
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In the text

$\begin{figure} \par\includegraphics[width=8.2cm,clip]{H4135_F9.eps} \end{figure}$ Figure 9: Dust mass production rates for different model parameters. Upper panel: dust size distribution parameter M = 1.8 and N =3.3, 3.6 and 3.9. Lower panel: N = 3.6 and M = 1.8, 7.2 and 68.4 The parameters N and M correspond to a peak in the dust size distribution at 0.15 $\mu$ m, 0.3 $\mu$ m and 2 $\mu$ m. The values for the preferred parameters (M = 1.8, N = 3.6) are shown (dots) and power law fits to the dust production rates calculated with the different parameters are plotted.
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In the text

$\begin{figure} \par\includegraphics[width=14.2cm,clip]{H4135F10.eps} \end{figure}$ Figure 10: Af $\rho$ to gas mass ratio (upper panel) and dust to gas mass production ratio (lower panel). In the lower panel, dust to gas mass ratios from other publications are shown. The values from Weaver et al. (1999) are calculated from the given dust production rates. Solid line postperihelion: linear fit to the dust to gas mass ratios from this work, computed with the prefered parameters. Dotted lines postperihelion: linear fits to the dust to gas mass ratios from this work, computed with model parameters as in Figs. 8 and 9. V & C (1999) stands for Vasundhara & Chakraborty (1999).
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In the text

$\begin{figure} \par\includegraphics[width=8.8cm,clip]{H4135_F1.eps} \end{figure}$	Figure 1: Reflectivity, $\tilde{{\cal R}}$ , of the coma of comet Hale-Bopp on January 20/21, 2001, averaged over 4600 km projected nucleocentric distance both sides of the nucleus and normalized at a wavelength of 6000 Å. The signature at approximately 5600 Å is a remnant of a night sky emission line. The "blue'' and "red'' intervals as described in the text are marked.
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$\begin{figure} \par\includegraphics[width=8.8cm,clip]{H4135_F2.eps} \end{figure}$	Figure 2: Spatial reddening profile for August 28/29, 2000. Filled symbols show the reddening on the "blue'' interval (4100 Å to 5400 Å), open symbols on the "red'' interval (5400 Å to 6100 Å) along the slit versus projected distance from the nucleus. Negative distances denote the sunward side, positive distances the tailward side of the nucleus.
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$\begin{figure} \par\includegraphics[width=8.8cm,clip]{H4135_F3.eps} \end{figure}$	Figure 3: Mean reddening in the coma of comet Hale-Bopp, for the "blue'' wavelength interval (top panel) and the "red'' interval (lower panel). Filled and open symbols mark data derived from the sunward and tailward side of the coma.
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$\begin{figure} \par\includegraphics[width=8.8cm,clip]{H4135_F7.eps} \end{figure}$	Figure 7: Dust production rates, determined with the model described in Sect. 5. Filled symbols show mass production rates (left scale), empty symbols production rates by number (right scale).
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