Excitation temperatures, T_ex (colour lines), and SiO fractional abundances, χ(SiO) (symbols), derived for the ambient, moderate and high-velocity regimes (vertical dotted lines) observed towards several offsets in G035.39−00.33. We consider v₀= 45.0 km s⁻¹. The errors associated with T_ex are estimated to range from 15 to 35 per cent.