Residuals maps and transmission spectra around the H_α line (left) and He I triplet lines (right). Top panels: residual maps in the stellar rest frame. The planet orbital phase is shown on the vertical axis, the wavelength is on the horizontal axis, and the relative absorption is colour-coded. The dashed white horizontal lines indicate the first and fourth contacts. The cyan lines show the theoretical trace of the planetary signals. Bottom panels: transmission spectra obtained combining all the spectra between the first and fourth contacts. All the wavelengths in this figure are referenced in a vacuum.