Methyl cyanide spectra obtained by integrating the emission inside the 3σ contour level area at 2.7 and 1.4 mm towards G10 as seen with the PdBI. We show in the top CH₃CN (12–11), in the middle CH₃CN (6–5), and in the bottom CH₃CN (6–5) vibrationally excited (v₈ = 1). The different K-components (top and middle panels) are marked with dashed lines in the upper (lower) part of each spectra in the case of CH₃CN (CH₃¹³CN). Different K-components of a same transition may have different spectral resolution because they were observed with different correlator units. Only the analyzed lines are labeled.