All Figures

Figure 1: In the upper panel, the full line displays the continuum-normalized spectrum of our giant star HD 2665 (including telluric lines, mostly water vapor lines) and, as dots, the continuum-normalized spectrum of our rapidly rotating B-star, which shows only telluric absorption lines. In the lower panel, the HD 2665 spectrum is divided by this telluric spectrum, resulting in a pure stellar spectrum of HD 2665. The sulfur lines and the Paschen  hydrogen line emerge clearly after the division. Magnesium and iron lines are also marked. The abscissa and ordinate scales are the same in both panels. Observe that the local continuum of the HD 2665 spectrum is fitted with a low order function, to avoid eliminating the wings of the hydrogen line. This will be even more important for the dwarfs.

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In the text

Figure 2: Continuum-normalized spectra of our programme giants: HD 2665, HD 88609, HD 111721, and HD 165195. Telluric absorption lines are ratioed out, but some residual signatures are visible. In the spectra of HD 2665 and HD 111721 several Fe  I lines and a Mg  II line are discernable and in the spectrum of HD 165195 the most conspicuous Fe  I line is detected. In the lower right panel in Fig. 3 identifications of all observable metal lines in this wavelength region can be found. Our best model spectra are also plotted with full lines. See text for a comment on the bad fit of the hydrogen Paschen line in the spectrum of HD 165195. After the names the star-model's temperature, , metallicity, and microturbulence are indicated.

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In the text

Figure 3: Continuum normalized spectra of our programme dwarfs: HD 19445, HD 84937, HD 94028, HD 132475, HD 201891, and HD 201889. The telluric absorption lines are removed as well as possible, but some residuals remain, most prominently in the spectrum of HD 19445 and HD 84937. Metal lines have been identified in the spectra of the four lowest panels. In the spectrum of the most metal-rich star, HD 201889, all the identified Fe I, Mg II, and S I lines are marked. The full lines represent our modelled spectra. After the names the star-model's temperature, , metallicity, and microturbulence are indicated.

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In the text

Figure 4: This figure shows the Galactic chemical evolution of sulfur. The iron and sulfur abundances, as we have determined it from analyzing Fe II lines and sulfur lines in the NIR, are presented with star symbols. Typical errorbars for our measurements of 0.15 dex, both for [S/Fe] and [Fe/H], are indicated. Circles indicate the sulfur and iron abundances derived by Israelian & Rebolo (2001) and squares display values found by Takada-Hidai et al. (2002) (including an upper limit which is illustrated with a triangle). For the 6 star we have in common with Israelian & Rebolo (2001) and Takada-Hidai et al. (2002), we have connected our new determinations with their measurements, which are based on the sulfur  lines. We have also plotted sulfur abundances derived by Nissen et al. (2003a) and Chen et al. (2002) for southern stars. These are plotted with crosses.

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In the text