Observed H₂CS, and H₂C³⁴S spectra (in T_B scale, see Table 1) extracted at the emission peak: α₂₀₀₀ = 03^h29^m03.^s75, δ₂₀₀₀ = +31°16′03.′′8. Transitions and corresponding upper level energies are reported. The vertical dashed line stands for the ambient LSR velocity (+8.6 km s⁻¹, Chen et al. 2009). Red labels and red vertical segments denote two H₂CS profiles with the same E_u value and blended at the present spectral resolution (Table 1). The black vertical labels indicate that the line is reported in another panel of the present figure. The H₂CS doublets at E_u = 244 K could be contaminated by CH₃OH emission with E_u = 317 K (see Table 1). The H₂C³⁴S(6_1,5–5_1,4) profile has been observed using both low- (black histogram) and high-spectral (blue) backends (see Sect. 2: labelled Widex and NB, respectively).