Black lines represent observed spectra of vinyl cyanide and its isotopologues (¹³CH₂CHCN, CH₂¹³CCN, CH₂CH¹³CN, CH₂CNC¹⁵N, and CH₂CDCN). Unblended transitions are noted in red, whereas blended transitions are given in black. The solid red lines represent the Gaussian fit of the unblended transitions. LTE spectra (LTE2) are shown in blue by considering N(H₂) = 1.35 × 10²⁵ cm⁻², an excitation temperature of 15° K, average source size (average of emitting regions of unblended transitions), and the average FWHM (obtained from the unblended, optically thin transitions) of the species. The column density of the species is varied until estimated good fits are obtained by eye. The red dashed lines show the systematic velocity (V_LSR) of the source at ~ 68 km s⁻¹. In addition, the name of the species and their respective transitions (in GHz) are provided in each panel.