Spectral bin transit light curves obtained with the G430L grating on HST/STIS. The light curves have an arbitrary offset in relative flux and are ordered by wavelength (see Table 4). Here, the bin at shortest wavelengths is located at the top (lightest in color in the figure) and the bin at the longest wavelengths is located at the bottom (darkest in color in the figure). The individual photometric errors are scaled with the standard deviation of the residuals and further increased by β, as describedin Sect. 3.4. Left: light curves overplotted with the best-fit combined model. Middle: light curves corrected for systematic effects, with the best-fit transit model overplotted. Right: residuals.