Continuum-subtracted VIRTIS-H spectrum of dataset H1 (blue curve) superimposed on the synthetic model that best fits the HB (2.774–2.910 μm) spectral region (orange curve). Dataset H1 is the weighted average of 22 data cubes obtained near perihelion (see Sect. 3.5.3 and Table 1 for geometric parameters and fitted parameters). The spectral range used to fit the HB region is indicated with a dotted green line. The bottom panel shows a synthetic optically thin spectrum at T_rot = 116 K, with different colours for the v₁ (green), v₃ (grey), and hot bands (red).