Fig. 2.
In (a), the observed H2S abundance is plotted as a function of visual extinction in TMC 1-C (blue), TMC 1-CP (red), and Barnard 1b (green). In a similar fashion, in (b) the observed H2S gas-phase abundance against the H number density in TMC 1 and Barnard 1b cores is shown. Crosses represent upper bound values. Finally, (c) displays the H2S abundance plotted against the gas kinetic temperature.