Spectral profiles of the GJ 3470 Si III line and N V doublet. Each row corresponds to a visit. Black histograms show the observed spectra, fit over points with black error bars. The green lines are the best fits for the intrinsic stellar line profile, which yield the red line after convolution with the STIS LSF. Gray bands delimitate the 1σ envelopes of the best-fit profiles. Vertical dashed lines identify the lines transitions in the Sun rest frame.