Lines of the linear ³Σ⁻l-SiC₃ radical observed in this work, with their fitted line profile shown in red. Features from other species are labeled in blue. The abscissa corresponds to the rest frequency (in MHz) adopting a v_LSR of –26.5 km s⁻¹ (Cernicharo et al. 2000). The ordinate corresponds to the antenna temperature corrected for telescope losses and atmospheric attenuation (in mK). Fully blended lines are indicated by a red star in the upper-right corner of the first panel. Quantum numbers are N (rotational quantum number) and J (total angular momentum, J = N, N ± 1). They are written as N_J.