All Figures

	Figure 1: Visible spectrum of 2004 DW, normalized at 0.55 m. The V-R and V-I colors derived by Rabinowitz et al. (2004), transformed in spectral reflectance, are also shown on each spectrum as white triangles. The spectrum is in perfect agreement with these color indices.
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In the text

Figure 2: Infrared spectra of 2004 DW. We show both the spectrum obtained during the 1-2 March night (lower spectrum), and that acquired the 29 February-1 March night (upper spectrum). This last one has been gaussian filtered to improve the signal to noise ratio and could be affected by errors in the extinction correction process, as explained in the text (we also cut the data in the 1.8-2 m region due to an incomplete removal of the strong telluric water band). The spectra have been normalized at 1.25 m and the upper one is shifted of 1 for clarity. The water ice absorption bands around 1.5 and 2 m are clearly visible on the March 2nd spectrum, and seem to be present also on the March 1st one.

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In the text

Figure 3: Visible and near infrared (March 2nd data) spectra of 2004 DW (normalized at 0.55 m) with superimposed two different compositional models. The dashed line shows the model composed by 38% of kerogen (10 m size), 60% of amorphous carbon (10 m size), and 2% of water ice (20 m size), corresponding to an albedo of 0.044 at 0.55 m. The continuous line shows the model composed of 4% Titan tholin (7 m size), 85% of amorphous carbon (10 m size), and 11% of water ice (10 m size), corresponding to an albedo of 0.102 at 0.55 m.

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In the text