Combined FORS2 spectropolarimetric observations of the Hα line in IRAS 17163 obtained on 4 and 8 July 4 2023. The data are unbinned and continuum-subtracted. The polarisation spectrum (top panel) has been corrected for polarisation bias. The red line in the top panel represents the flux spectrum. The light blue shading indicates the wavelength range 6550–6576 Å used for plotting the Hα line in the Q–U plane (bottom panel).