Variation of the predicted opacities of the CS (2–1) (filled symbols) and CS (3–2) (starred symbols) transitions as a function of the molecular hydrogen density in the diffuse and translucent cloud conditions computed with RADEX using the column densities and FWHM listed in Table 3. The colors show the kinetic temperature from 10 to 60 K, and the H₂ ortho-to-para ratio scales with the kinetic temperature. The symbol shapes indicate the electron fraction as follows for the CS (2–1) line: lower than 2 × 10^-5 filled triangles, between 2 × 10^-5 and 10^-4, small filled squares, and filled circles for 2 × 10^-4. A similar progression is used for the CS (3–2) line, lower than 2 × 10^-5 crosses, between 2 × 10^-5 and 10^-4, small stars, and 8-branch stars for 2 × 10^-4. The measured opacities for the four detected velocity components are shown with the dashed and dotted gray areas, from top to bottom: −17.2 km s^-1, −10.3 km s^-1, −8.5 km s^-1 and −4 km s^-1.