... molecules

Tables 3-5 and Fig. 1 are only available in electronic form at http://www.edpsciences.org

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... sulphur

van der Tak et al. (2003) argued that the non detection of the 25 $\mu$m line corresponds to an upper limit to the atomic sulphur of $\leq$ $5\times 10^{-8}$, computed by considering line absorption. Indeed, this is an upper limit on the S abundance in the absorbing gas, i.e. the foreground cold gas, rather than the hot gas. The upper limit on the emitting hot core gas is much higher, as explained in the text.

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